MAY
1916
RECESS
35p
TANGO
SWING
MARCH
.SRADIO
CHART
IO
&_
rt
.owrtPa
1'
4i4
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SAMBA
MAMBA
CHA CHA
WALTZ
ROCK
FOXTROT
SHUFFLE
with
riratur
1140081
FIÍI1tI
I ET[11S
róGROVE KS.
T.525.
`É ISE
ADD SR VAT TO PRICES MARKED
ADD 26UVAT TO ALL OTHER PRICES
OR AS CURRENT VAT LEGISLATION.
SEND C.W,O.(EXCEPT GOVT DEPT)
POST
PACKING 20P FOR THE UK.
BARCLAYCARD & ACCESS BY POST,
A
OR
£5 MIN ON TELEPHONE
ORDERS.
CATALOGUE LIST FREE SEND SAE.
MONEY BACK IF NOT SATISFIED,
yCIJ WON'T EEEI EV E CUL [MICES
'I
IC's
OPTO ELECTRONICS
ALL FULL SPECIFICATION LED
DL707 LITRONIX CON ANODE &
DL704 LITRONIX COM CATHODE
0,3' 0 -9 &.DEC POINT 89pea
*
DL747 JUMBO DISPLAY 0,6"
LED o -9 DP.COM ANODE £1,75
*
3015F FILAMENT DISPLAY
.DISCO ETC STROBE TURF
£1.25*
£5.ea*
F'ED LEAS iip
209 STYLE OR 0,2" NO CLIP
TIL209 or 0,2 "RED A CLIP
GREEN LED LARGE OR SMALL
ORANGE LARGE OR SMALL
11p*
13p*
22p*
22p*
ORP12 57p* 255777 33p*
TEC12 IC PHOTO DETECTOR
81p'
ICL8038
£2.69*
LM300
£1,50*
LM301 OPA
41p*
LM304 0-40V £3*
LM308 HS Bo 95p*
LM309K 5V £1,75*
IF £2,00
LM372
£3
LM377 2x2W
LM380 60745 89p
LM381
12
LM3900 40PA 63p*
MC1303
£1.47
MC1310
£2.09
MC1312 SQ £1.50
£2,50
MC1318
MC1330
75p
MC1339
£1.49
MC1350/1/2 75p
13
MC1466 /9
59P
MFC4000 }W
NE536 FETOPA £2*
NE540
E1,10*
NE550 2vR'
£1 *
NE555 TIMER 41p*
84p*
NE556 2x"
NE560 PLL £4,00
NE561 PLL £4,00
NE562 PLL £4.00
NE563
£2,25
£2,50
NE565
NE566
11,55
NE567
12.20
SN72741 741 20p*
SN76660 IF 75p
SN76611 IF £1
TAD100 &IP £2
TBA800
89p
TBA810 7WAF 80p
TBA820
[1.49
PRICE EACH:AC127 & 128 lOp*
15p*
AC176
AC187 & 188 18P*
AD149
45p*
MATCHING
20p*
ISS.SUSB SET 6p*
TIP29 A 30 43p*
TIP31 a 32 54p*
AD161 & 162
BC107
TIP42
TIP2955
TIP3055
TIS43 UJCT'
ZTX107/8/9
ZTX300 5304
ZTX500 &504
2N706 & 708
2N2646 UJT
2N2904 B 5
2N2926broyp
2N3053
ZN414
+1PU131
RX
BC1073
BC108
63p*
67p*
99p*
67p*
26p*
llp
20p
42p
lip*
38p*
20p*
9p
16p*
2N3054
42p*
2N3055 115W 37p*
2N3055 RCA 60p*
2N3702/3/4/5 8p
BC108B
BC109
BC109C
BC147J8/9
BC157/8/9
12p
BC167/8/9
BC177/8/9
18p
BC182/3/448L10p
BC212/3/4A8L12p
16p*
BCY70/1/2
BD131
& 132 39p*
BFR88
BFY50
250V 35p
89p*
64p*
49p
MJE2955
MJE3055
PUT
CD4001
CD4002
CD4009
CD4011
CD4013
CD4016
CD4017
CD4018
CD4022
CD4023
CD4024
CD4027
15p*
16p*
16p*
45p*
17p*
45p*
45p*
82p*
82p*
77p*
l6p*
63p*
45p*
DIGITAL CLOCKS
CD4028
CD4046
CD4047
CD4049
CD4054
CD4055
CD4060
CD4071
CD4081
CD4510
CD4511
CD4528
CD4558
1
73p*
£1
*
73p*
45p*
94p*
£1
90p*
17p*
17p.
£1.19*
£1.90*
£1.10*
[2.35*
MM5314 £3,39*
MM5316 ALARM,E5tMM5311
series
7400N
7401
9p*
lOp+
7402/3
11p*
7404
13p*
7405/6/7 25p*
7408/9/10 9p*
7411/12 20p*
7413
26p*
27p*
7417
7420/27
26p*
7430/32 16p*
7440
12p*
7441
64p*
7442
59p*
7445
75p*
7447
67p*
7450/3/4 1213*
7460
12p*
7470
26p*
7472
22p*
7473/
26p*
7474
25p*
7475
44p*
7476
28p*
40n*
7480
95p*
7481
72p*
7482
80p0
7483
£1.20*
7485
33p*
7486
12,70*
7489
37p*
7490
£5.00*
36PINS 28p *FACE CUTTER49p*
COPPERCLAD 0.1 PITCH VERO
AUDIBLE WARNING BLEEPER
12VOLT 35mA,SPARKLESS £l'
DALO ETCH RESIST PEN
FEC ETCH PAK 500gm
6x4" COPPER BOARD
PCB KIT 3 ITEMS
69p*
89p*
50p*
£2*
CASSETTE MECHANISM
FEW AVAILABLE TOP LOAD £15
TELEPHONE
54525
50p*
43p*
7493
7495
7496
74100
74107
74120
74121
74122
74123
74141
74143
74147
74151
74154
38p*
58p*
68p+
FET3819 I4P
741 20P
NE
555 42p
7400N 9p
£1
*
30p*
£1
*
26p*
42p*
58p*
64p*
12
£2
65p*
£1.30*
TGS GAS DETECTORS
£2 eat
LOGIC PROBE FOR TTL etc £5*
HEATSINKS TO5/18 7p, *T03 15p*
TV4 PLASTIC POWER 16p*
TO3 EXTRUDED 4" FINNED 39p*
DIN PLUGS ALL 12p.SOCKETS 9p.
ALI CASES AB5 /AB7 50p* AB13 69p*
A913 69p* AB9
59p+ AB12 40p*
TRANSFORMERS 10omA 6,9 or 12V 89p*
TRANSISTOR TESTER
TTC TESTS ALPHA,BETA Ico
NPN /PNP A DIODES NOW £13*
£3.49*
C1000 MULTIMETER
BENCH POWER SUPPLY P1076
ONLY £3.99 *
3 -12V lA
ALL ANTEX SOLDERING IRONS
cassettes
IIA /lA
6/12 or 12/24
12 ea
OA91 GERMANIUM 5p.
5p*
1A50V A 104002
6p' 194007
9p*
a 1N914 SILICON 4p.
BZY88 400mW
9p.
11W 17P,Z1Jnoiee£1
RECTIFIER 1A50 18p
25p. 4A100V
45p
ZENERS
ZENERS
BRIDGE
1A400V
74155
65p*
74157
90p*
74160/1 95p*
74162/3 95p*
74164
£1.20
74165
£1.20
74175
95p*
74180
E1 *
74181
12 *
74185
£3 *
74190 £1.40*
74193 11.10*
74195
75p*
74196
E1 *
74197
E1 *
74198/9 12 *
POTENTIOMETERS
LIN OR LOG 2,2K to 1 MEG. 16p
PRESETS 6p.RESISTORS 1p,ea IN
21 "x5" 32p' 211"x31" 29p*
31 "x5" 37p* 31 "x31" 32p*
31 "x17" £1.70*
31 "x17" PLAIN 0.1 "11.06*
peño It1p
7491
7492
SCR'S
*
LOW NOISE NOT REJECTS.
C60 33p ea TEN FOR £2,70
C90 42p ea TEN FOR £3,65
TRIACS
SCR's TAGI /400 15400V 4Op)
1550V
25p *1A 600V
65p*
C106D 45400V SCR ONLY 47p
TRIAC SC146D 10A 400V £1.
10A 400V Int.Dfáp
£1.25*
16A 400V DISCO TRIAC 11,75'
16A 400V Int.D1ac
£2,*
BR100
25p*
DISCS:
BULK OFFERS PER 100off each
154001 12,50* 1N4004 13,50
AC128
110 * AC176
£12
'
BC107 16.80* BC108
16,80'
BC109
17,00* 253055 £27
NE555 137 * 741C(8)£18
.
vero
12*
109 8p
BFY5I I4p
OA81 a
1N4001
1N4004
1N4148
TTL ID's
CAPACITORS
CERAMIC 22pf to 0.1 of 50V 5p.
ELECTROLYTIC,IN 10,25 A 50V.
2UF /10V ,10,50, & 100uí 25V
A 10V 7p ea, 50VOLT
lop ea.
1000 of 25V 18p.200 /500uí 9p.
AY51224 4DIGIT £3.49 *PCB 11,*
LED DISPLAY PCB 4DIGIT 75p*
DIL BREADBOARD 6x4"
BC
293706/7/8/9 8p
2N3710 A 11 8p
2N3819E FET 12p
2N3820 FET 40p
2N3823E FET 16p
2N3904J5J6 15p
2N4289 mini 31p
2N5457 FET 45p
14p*
14p*
BFY51
BFY52 & 53 14p*
BSX19/20/21 l6p*
MJ2955 TO3 75p*
99p
2N305 S 37P
TIP41
33p*
8p*
12p*
7p*
12p*
8p*
12p*
9p
12p
NEW MOTOROLA
CD4000
PRICES
DIODES
í4F1
CiT1OS LOGIC
ro
TRANSISTORS
PRICES
¿ OW
26p
22p*
28p*
DIL 14
31p*
Regul'r 45p*
20p*
DIL 8
DIL 14 31p*
TO99
31p*
67p*
747 2x741
748 DIL B
27p*
£1.39*
7805 5V
7812 12v £1.39*
7815 15V
£1,39*
7900 Series £3 *
76013 6W AF 75p
CA3046
59p
CA3048
12.20
CA3054
12
RF/IF
T099
DIL 14
ADD VAT
FULL SPEC. DEVICES,
NO REMARKS REJECTS,
OR FLOORS VEEPINGS.
QUALITY PRODUCT
703
709
709
710
723
741
741
741
NORMALLY 24 HOURS
ON EX STOCK ITEMS.
MIA
LN'
BARGAIN PAKS
molto* Full spec.
PAK
PAK
PAK
PAK
PAK
PAK
NEW
10 RED LEDS our choice Eí*
B
5 741C OP AMP 8 PIN
£1*
C 4 253055 £1 *.D 12 BC109£1*
E 10 BC182 £1,F 11 293704 11
8 BFY51 £1 *,11 9 2N3819e£1
G
J 9 2N3053 £1 *,K 40 1N914 £1
PAK M 4 PLASTIC 3055 90W 11*
A
OIL
sockets
TOP QUALITY NYLON
SOCKETS,HALF PRICE
OR 16 PI N 12p+
8,1 4,05
SOLDERCON PINS:
100 65p *1000
13,50
SLIDER CLEARANCE WHILE
STOCKS LAST ALL 10p ea,
PRACTICAL
VOL. 52
NO.
1
ISSUE 831
WIRELESS
MAY 1976
BRITAIN'S PREMIER MAGAZINE FOR THE DO -IT- YOURSELF RADIO AND ELECTRONICS CONSTRUCTOR
EDITOR
Lionel
E.
NEWS & COMMENT
Howes, G3AYA
ASSISTANT EDITOR
Eric Dowdeswell, G4AR
ART EDITOR
Peter Metalli
PRODUCTION & NEWS EDITOR
Colin Riches
TECHNICAL SUB -EDITOR
Bill Tull
TECHNICAL ARTIST
Alan Martin
SECRETARIAL
34
38
46,
47
58,
60
65
70
73
Karen O'Neil
Jill Austin
78
ADVERTS MANAGER
01
-261 5762
Colin
R.
Brown
Advertisement
enquiries to
,
-
Roy Smith
-261 6275
CONSTRUCTIONAL
CLASSIFIED ADVERTS
01
... NEWS ... NEWS ..
BOOKS RECEIVED
LETTERS -readers voice their views
57 HOTLINES on recent developments- Ginsberg
NEXT MONTH IN PRACTICAL WIRELESS
59 PRODUCTION LINES -news on products of interest
Colin Riches
CQ! CQ! CO! CQ! CQ!
P.W. READERS' PCB SERVICE
TELEVISION -contents of our 'sister' magazine
ON THE AIR-Amateur Bands -Eric Dowdeswell, G4AR
Broadcast Bands SW -Derek Bell
Broadcast Bands MW- Charles Molloy
KINDLY NOTE -notes on published articles
24, 25 NEWS
correspondence and
Advertisement
the
Manager,
Roy
Smith,
Practical
Wireless,
Kings
Reach
Tower,
Stamford Street, London, SEI 9LS
Published by IPC Magazines Ltd.,
Fleetway House, Farringdon Street,
Tel. 01 -634 4444
London EC4A 4AD.
-F.
26 3 -BAND R.F. MINI AMPLIFIER
G. Rayer
29 TAKE 20, No. 74 (Snap Machine) -David Andrews
32 A.F. SIGNAL SOURCE -W. Mooney
48 RHYTHM GENERATOR
S. Webb B.Sc.
66 SIMPLE LOGIC INDICATOR -Peter Hemingway
-A.
OTHER FEATURES
30
31
BINDERS
Binders (£2'10 from May 1st) and
indexes 45p (inc. VAT) can be supplied
by the Post Sales Department, IPC
Magazines Ltd., Lavington House,
25 Lavington Street, London, SE1 OPF.
BACK NUMBERS
We regret that we are unable to supply
back numbers of Practical Wireless.
Readers are recommended to enquire
at a public libi ary to see copies. Requests for specific back numbers of
Practical Wireless and Television can
be published in our CQ Column.
37
41
62
69
TECHNICROSS -Puzzle No. 13
SPECIAL PRODUCT REPORT -Bi -Pre -Pak 'Super Spark'
Capacity Discharge Ignition Kit
GOING BACK -Colin Riches
GENERAL SERVICING, Part3, Valve Radios -Les Lawry -Johns
ECONOMY CONVERSIONS -B. B. Rafter
IC OF THE MONTH -Motorola MC1312P Quadraphonic
Decoder
EXTRA THIS MONTH!
DOUBLE -SIDED RADIO SERVICING CHART
COPYRIGHT AND QUERIES
© IPC Magazines Limited 1976. Copyright in all drawings, photographs and articles published in "Practical Wireless" is fully protected and
reproduction or imitation in whole or in part is expressly forbidden. All reasonable precautions are taken by "Practical Wireless" to ensure
that the advice and data given to readers are reliable. We cannot, however, guarantee it and we cannot accept legal responsibility for it.
Prices are those current as we go to press.
We regret that we cannot answer technical queries by telephone nor can we provide information or advice on manufacturers' products other
than that given in the magazine. We will endeavour to assist readers who have queries relating to articles published but we cannot offer
advice on modifications to our published designs. All correspondents expecting a reply should enclose a stamped addressed envelope.
Practical Wireless, May 1976
I
CLEARANCE OFFER!
PANEL METERS
AT GREATLY REDUCED PRICES
BAKELITE PANEL METERS -MODEL MR 65
Dimensions: Front 80mm x 80mm square
Panel Hole: 65mm diameter
Accuracy± 2.5%
AS ABOVE LESS SPEAKERS
RANGES
1-0-1 mA
5mA
10mA
50mA
100mA
tÁ DC
30V
50V
2A DC
150V
300V
500V
£295
25uA
504fA
VU Meter
P/P + Ins.
Moving iron (all others are moving coil).
each
£3.05 each
£3.25 each
£3.40 each
15P
PHONE
MIC., JACK.
JACK. MONITOR VOL.
MONITOR
CONTROL.
SELECTOR DECK (1) Vol.
Control. DECK (2) Vol.
control. Mic. Vol. Control.
Treble Control. Bass Control ON /OFF Switch. Neon
Indicator. Twin Turntables.
Terms: Dep. £795 and 18 fortnightly paymts. £3.33. Total £67. 89.
CLEAR PLASTIC PANEL METERS -MODEL MR 85P
Dimensions: Front 110mm
x
wide
120mm
Panel Hole: 85mm
Accuracy ±2.5%
200M
'S' Meter lmA
each
£4
VU Meter
P P + Ins. 15p.
55
each
£4.55 each
500aA
50-0-50PA
100-0-100mA
500-0-500pA
1mA
1 -0-1mA
5mA
Moving
10mA
50mA
100mA
500mA
1 A DC
5A DC
15A DC
30A DC
10V DC
20V DC
POWER (SLAVE) AMPLIFIER 100 WATT
Suitable for use with above or other
DISCO-Consoles.
Also for increasing output
of lower-powered Ampli-
RANGES
500A
1000A
£3.95
50V DC
150V DC
300V DC
15V DC
300V AC
fiers. Terms: Dep. £9.00 and 8 mthly
payments of £5.22 (Total £50.76) carr. £1
TITAN GROUP/DISCO SPKRS
GUARANTEED FOR
1A AC'
5A AC'
10A
20A
30A
on (all others are moving
AC'
AC'
AC'
coll).
EDUCATIONAL METERS -MODEL ED 107
Imp.8-16
High quality moving coil meters ideal for school use and many other implicit_
(Ions.
Housed in strong black plastic cases.
Clear view front. 3' mirror scale. Fully
insulated terminals will accept either spade
or 4mm plug.
Dimensions: 100mm wide a 90mm deep x
105mm high overall.
Accuracy 12%
SINGLE RANGE MODELS
5A DC
SV DC
10V DC
1mA
-0-1
FOR ONE MONTH ONLY
FANE CRESCENDO
12 IBABB
our
12" Super
Guitar Speaker
Bass
Price
Carr. Free
133.95
£49.30
£5.95
DUAL RANGE MODELS
5V/15V DC
1A15A DC
each
P,'P h Ins. 150
Available for personal shoppers at LASKYS
111,441EYS
01-493 8641
01- 2620387
01-836 0845
01-437 8204
Oxford Street, W.1.
Edgware Road, W.2.
Tottenham Court Road. W.1.
Lisle Street. W.C.2
481
311
42
MAIL ORDERS AND ACCOUNT ENQUIRIES TO
OFFICE.
FFICE.
LASKYS.
OF CUSTOMER SERVICES DIVISION,
DEPT. 'J' AUDIOTRONIC HOUSE, THE HYDE
HENDON, NWO 6JJ.
Telephone: Mall Order
(24 hour anawerphone)
Telex:
924920
01
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or 01.210
Accounts:
01 -200
0037
0444
Access, Barclaycard and Diners Club accepted at
all branches or by telephone at head office.
ALL PRICES INCLUDE VAT.
2
YEARS
MODEL
Model
Model
Model
Model
Model
Model
Model
£14.00
£21.00
£36.00
£27.00
£28.00
£39.50
£44.00
MOIfTHLY PAYMENTS
DEPOSIT
at £282
(Pr) 1490 a
at £3 07
(Pr) 1090 a
at £310
(Ea) 14-£9 a
at 2225
(Ea) S819 a
at £237
(Ea) £4-96 At
at £337
(Ea) 1000 A
(Ea) £085 ffi ft :.t £337
TERMS
T12/35
T12 /60
T12 /100
T15 /60
T16/70
T16 /100
T18 /100
£10.95
£14.95
£23.95
£17.99
£19.95
£28.95
£29.95
TOTAL
£2588
£3386
£28 05
£21 90
£2391
£3298
£3391
FULLY GUARANTEED. Imp canted and leterlsav d tabors aacswarr.
Primulas 500-680e. 50./s. ber seed ALL PRICES INCLUDE VAT
OUTPUT TRANSFORMERS
MIDGET CLAMPED TYPE
Standard Pentode 6000 to 3 ohm,
£176
250v. 60mA 6 3v. 2a.
or 7000 ohm to 3 ohm £1.12.
11.85
250.0.250v. 60mA 6.3v. 2.
Push Pull 8 watts EL84 to 3 ohm
MOUNTING
UPRIGHT
FULLY SHROUDED
or 16 ohm £1418; Push Pull 10 -12
£500
250.0 -260v. 60mA 0.3v. 2a. 0-5.8.3v. 2a.
250 -0 -250v. 100mA 6.3v. 4a. 0- 6 -8.3v. 3s.
300.0 -300v. 130mA 6.3v. 4a. C.T. 8.3v.
la. for Mallard 510 Amplifier
360 -0-3150v. 100mA 8.3v. 4e. 0- 5 -6.3v.
14.55
16.80
3. «'U
350.0 -350v. 160mA 6.3v. 4a. 0.5 -6 3v. 3. £6.80
420- 0.425v. 200mA 6.3v. 4a. C.T. 5v. 3a. 8985
425 -0 -425v. 200mA 8.9v. 4a. 03v. 4a. 6v. 3a.
919(0
3
5
T12/35 12" 35w
T12/60 12" 60w
T12/100 12" 100w
T15/60 15" 60w
T15/70 15" 70w
T15/100 15" 100w
T18/100 18" 100w
R.S.C. TRANSFORMERS, L.F. CHOKES & RECTIFIERS
mA
500mA/5A DC
5V/50V DC
C2
SPECIAL OFFER
Rec. Ret. Price
15V DC
20V DC
60V DC
300V DC
1A DC
100gÁ
50-0-50uA
f79.95
MOBILE DISCO CONSOLE £59.95
500mA AC
50mV DC
100mV DC
AC'
AC'
carr. £3
Terms: Dep. 8900 and 18 fortnightly payments 5461 (Total 80118).
AC'
AC'
AC'
IA AC'
SA AC'
10A AC'
20A AC'
30A AC'
59A AC'
5A DC
10A DC
15A DC
30A DC
50A DC
5V DC
10V DC
15V DC
20V DC
50V DC
150V DC
300V DC
100uA
500uA
50-0-50uA
100.0-1008A
500.0-500uA
1mA
carr. £3
-e
Consisting of Twin
Turntable Console
with Pre-Amp and
built -in Power Output.
Sep. vol. controls for sac T/table. H /phone
monitoring facilities. Sep. Bass and Treble controls. Mic. Vol. control. Neon Mains Indicator. Plus Pair 12" Spkrs. in
matching Rexine covered cabinets.
Terms: Dep. £15.99 and 18 fortnightly paymts. £5.41. (Total £113.37)
ass.wwiao
a)
MUNI
460.0 -460v. 250mA 8.3v. 4a. C.T. 6v. Sc. 11046
TOP SHROUDED DROP- THROUGH TYPE
12 10
260.250v. 70mA 6-3v. 2a. 0- 6.8.3v. 2a.
02 90
260.0.250v. 100mA 8.3v. 9.65.
£3 20
260.0 -250v. 100mA 6.3v. 2a. 8.3v. la.
360- 0.360v. 80mA 8.3v. 2. 0- 5.6.9v. 2a. tá20
S4.86
0.5.08v.
Sa.
260.0.250v. 100mA 13v. 4a.
300- 0.900v. 100mA 61v. 4a. 0-5.08v. 85. £4.86
300.0 -300v. ISOmA 82v. 4e. 0.5.03v. la
£b 20
suitable for dullard 510 Amp.
350.0.360v. 100mA 8.3v. 4s. 0.5.8.3v. 35 14 85
350.0.350v. 150mA 6.3v. 4a. 0.11.8.3v. 35. 18.20
FILAMENT OR TRANSISTOR POWER PACE
Type: 12v. la. 91.10, 8.3v. 11a £100, 6.3v. 2a.
11-10 6.3v. áa 21.70,13.3v. 6.02 60,12v. 3a. or 24v.
1 Oa. 1280 0- 9.18v. 15a. 1220, 0-12-25-42v. Sa.
1210
AUTO (BMW/STEP DOWN) TRANIFORMER6
200 -990 -250v. 60.80w. 1290 150
0- 110/120v.
matte £5.20, 250 watts 6647, 500 watts U-84
HARGER TRANSFORMERS
0.9.15v. lia. 1908, 24a. 1286. 9a. 18.82, 0a.
6a.
8119, 8a. 1248
a84.
its 8v, 8 to 3 ohm or 16 ohm
Push Pull 10-12 watts
to match 8v. 8 to 3, 6, 8 or 15
ohm £872; Push Pull EL84 to
3 or 16 ohm 10-12 watt. 6211;
Push Pull Ultra Linear for Mollard 610 etc. 1435; Posh Pull
16 -18 watts, sectionally wound
8L0 KT88 etc. from 3 or 15 ohm.
13'71p. Push Pull 20 watt high
quality sectionally wound EL34
8L8 KT88 etc. to 3 or 15 ohm,
tally shrouded. £0.87p.
SELENIUM RECTIFIERS
F.W. (Bridged)
AU 6/12 v. D.C. output. Max. A.C.
£261;
input 18v.
lá 45p. 2.
4a 96P, Oa
1148.
57p, 3a 66p,
CHOKES 150mA, 7.1011,
won £125; 100mA, 10H, 20012
£1.10; 60mA, 10H, 40011 41p.
L.B.
HI -FI ITEMS
PREVIOUSLY ADVERTISED INC.
DISCOUNT LINES
ARE STILL AVAILABLE.
RSC PRICES INCLUDE VAT
Practical Wireless, May 1976
Units listed below
(a) DISCOMAJOR TWIN
WATT DISCO SYSTEM
LlK/r/oLi
TDI DISCO CONSOLE
with
integral 100W amplifier
Incorporating twin SSE MPH type
turntables and Sonotone or Aooe
Cartridges with diamond styli.
Separate Vol. controls tor each
(e) MATCHING 'MIKE'
turntable. Also NONITOBING
(d) PAIR SO WATT SPEAKERS FACILITIES,
Treble and
Black Rexine covered Bass Controls. plusSeparate
input
Cabinets Size approx. for 'mike' with vol. control.
TURNTABLE CONSOLE
J
(b) PAIR
e
OF HI -FI H'PHONES
"£159.95
18"x18 ">,8
(a) (b) (e) &
(d) Carr. £4.00
DEP. £19.95 & 18 fortnightly.
50 WATT
SPEAKER payments of 19.19 (Total 1185.37).
1155155111111111111111111
Or DEPOSIT 184.96 and
fortnightly pymte.
and POWER AMPLIFIER
Complete with Ild
SYSTEMS UP TO
DISCOMASTER
300 WATTS OUTPUT
TWIN TURNTABLE POWER CONSOLE
£155
FANE DISCO 60C SPKR
£119.95
£27.95
Incorporating two exceptionally efficient
13" x 8" speaker units. Dep. 6895 and 8
monthly payments 61.50 (Total 581.951
Carr. 850
INTEREST
.
'POP' 100
Watt
18" 100
3
14.000 gauss
speakers with high power volte coil,.
Sire approx. 64" x 14" x 11 ". Dep. 6900 k
5400
12 mthly pymte.
£49.95
(Total 557.001 Cart. 86p
REFUNDED
on Credit Purchases
settled in
SUPER MINSTREL IO
3
months
W GUITAR AMP.
Incorporating Tremolo and 10" Speaker. Output 10 watts
R.E.B. Contl000u.. S Jack Inputs for Nkrophone and Instrument.
Halos Neon Controls: Volume, Tone, Tremolo Speed. Tremolo
I
.
Teerms: DEPOSIT 17 78 and
B monthly
payments 43.40 (Total £3498) Carr. tree
RSC
FAN E
SPEAKERS
PULL RANGE
AVAILABLE AT
£6995
Extra high seneitivlty. Suitable for Bass Guitar.
Or Dep. 59.95 0 8 monthly payments 1870 (Total 679.651
Carr. 61.75
covered. Fitted with protective
corner pieces. Carr. 12.60.
Or Dep. 110.00 & 12 monthly payments
57.57 (Total £102.04)
or with
£88.00
L125 100 W TWIN SPKR UNIT
at
YORK
CARLISLE, DEWSBURY
and PRESTON
OPEN ALL DAY SATURDAYS (5 Day Weak)
B RADFORD 10 North Parade (Closed Wed.). Tel. 25349
B OLTON 23 Deensoate. (Cloud Wed.). Tel. 33512
BIRMINGHAM 30/31 Greet Western Arcade.
Tel. 021 -236 1279 (Closed Wed.).
CARLISLE 8 English Street. (Closed Thurs.). Tel. 38744
COVENTRY 17 Shelton Sq., The Preclnct.Tel. 25933
DERBY 07 St. Peter's Street. (Closed Wed.). Tel. 41361
DARLINGTON 19 Northgate (Cl. Wed.). Tel. 58043
DEWSBURY 9/11 KlnOswey (Closed Tues.). Tel. 488058
DONCASTER 3 Quesnsgste, Waterdale Centre.
(Closed Thurs). Tel. 83069
Practical Wireless, May 1976
Ei 0.99
Guitar use).
Terme for Paire: Deposit 1808
and 8 mthly paymts of 1875
(Total 125.98). Carr. free.
1800. Total 11119.90
PAIR BUITA BL N
ALL PUSPO BE 9
HIGH POWER
TWEETER PH50
Response 31C11.-20KHr
with 2 mid. Non elect
filter available 95p.
Allf
Imp 8 (I
60
Watt
£6.65
TITAN T2H HIGH FREQUENCY UNITS
ALL 2 -TONE VYNIDE & VYNAIR FINISH
L12/2 50 -WATT Fitted pair of 12"
35 watt high flux speakers. Music
rating 100w. Imp. 8-15 ohms. Carr.
11.50. Terms: Dep. 15.11 & 8
Monthly payments. of 25.11. (Total 145 99).
L12/50 12" 50 WATT 13,000 lines
15 ohms. Terms: Dep. 14.95 and
8
131 -91) ) Caer 55p.
13.37 (Total
JINGLE MACHINES JINGLE 8+
Employing Standard 8 Track
Cartridge Or Dep.
6455 & 8 monthly
pyts 14.85 (Total 145 85).
HEAVY DUTY CABINETS
1.
®
LIQUID WHEEL
from
£29'95
'SOUND TO LITE' SYSTEM
£ 106.95
PULSAR completpe kit
Black Vynlde covered. Fitted Protective
Corner Pieces. Out for various Speaker
Combinations. Carr. £1 each unit. Sizes
approx.:
E26.95
PROJECTORS
£37.95
£94.50
New Branches
monthly payments.
12.62 (Total 188.931
FOE BASS GUITAR. ELECT. ORGAN, ETC.
'POP' 25/T 12" 25W
£12.95
for pain Dep. 1690
k 8 mthly pymte
£39,95
Suitable for all purposes Inc. Baas Guitar
Carr. 12.50
Terms. Dep. 11460 a 18 fortnightly payments 4616 (Total £107.20)
ohm
6
HIGH QUALITY L'SPEAKER UNITS
FAL PHASE 50-4 AMPLIFIER 50 WATT
FAL PHASE 50-4 WITH LI2/2
70 W TWIN SPEAKER UNIT
Dep. 52.99 and
£35.95
Solid state. 4 Sep. controlled Inputs Plus master vol. control. Ind.
Base and Treble Controls. Protection against serious o/p overloading.
0/p for epkra. 8 to 16 ohms. Size 17" x 7" x 75 ". 200.250v. A.C.
mains 0 50w
R.M.S. Deposit 58.110
I.S.E.
& 8 mthly.paymenta 2676. Total 66460 Carr. Free
£4S'Ó0
8/16
*£19.99
and 8
Incorporating a pair of Highly Sensitive Horne with substantially flat
response to over 15 kHz. Rating
70/100 watts. Imp 8 or 15 0. Or Dep.
4.9(í a 8 monthly
payments ass
(Total 13999).
Carr. 55p
Rating 50 watts. 3 inputs, 2 vol. control. -Base, Treble Preseence. Carr. £150
Suitable for Lead or Rhythm Guitar, mio., Radio, Tape etc. Ina. High Flux 12"
80w Speaker. Dep. £7.95 & 8 monthly payments 1748 (Total £6779).
Vynlde
1111
SOT
12" 50 Watt
13,000 gauss
14.000 gauss
a /ISO
tthly payments
1460 (Total 14876)
Dual cone.
15 ohm Imp.
(NotforBaee
CRESCENDO
pr.
5 extra
'POP'
'POP' 60
Watt
15" 60
£38.95
Dep: SS
£59'95
PHANTOM 50 /GP .purpose version of above.
Ilcu of Lt1Ly/6r0 unite
SIISO
£29 99
PHANTOM 50 COMBO AMP.
£ I 25.00
payments 1671
Carr. £180
(Total £140781
Suppplk.lwIthabovein
UNITS
All power ratings are R.M.S. continuous. 2 YEARS' GUARANTEE
Gish flux ceramic magnets. ALL CARRIAGE FREE. SPECIAL PRIDE
IDEAL FOR VOCALISTS
AND PUBLIC ADDRESS
TYPE 04/00 70 WATTS. Fitted four
12" 26 watt Highly sensitive high flux
ALL RSC PRICES INCLUDE VAT
Terms DEPOSIT 120
and 18 fortnightly
FANE ULTRA HIGH POWER SPEAKERS & KITS
R.S.C. COLUMN SPEAKERS
All types 16 Ohms covered In Vynlde & Vynair
TYPE C 132 40-50 WATTS
OF ABOVE
Fabulous specialist range Spkre In heavy Vynlde covered for
cabinets with protective Corner pieces. List Price £87 00 pr.
Send
analooue
18.80 (Total117440.
£209.95
Carr. 100
!1149 (Total 128687)
Twin McDonald MP80 type turntables. Sonotone or Ara. cartridges with
Carr .
diamond styli. Faculties as TDI Console but with built -In 100 watt Power Am
£2 60
pltOer, complete with lid. Or Dep. 115'95 and 18 fortnightly pymts SS 78 (Total Slab 99)
fortnightly
or DEPOSIT
STEREO VERSION
TD2S STEREO VERSION
STEREO VERSION
of Above System
TWIN
URNTABLE
ITH PRE-AMP.
AT DB$ CAESSABLE
Blank
covered
Cabinet withh Rd.
Or DEP. 114 06 and
la fortnightly stymie.
6547 (Total £11841) Carr. s1 60
Dep. 41495 and IB fortnightly payts. 6595.
(Total 6121 69). Super SL Unit. 1000 watt
per channel. Manual override buttons 2
spotbanks with 6 bulbs (3 sep. colour.) 6 yd.
and 10 yd. leads, Stied plugs. Units sold sep.
FAL SOUND -TO -LITE UNIT í2I.60
18" x 18" x 9"
11096
24" x 24" x 12"
91096
ee 3 -WAY SPOT BANK
38" x 24" x 12"
/55'56
Each L16-20
Excluding Bulbs
1126.95
36" x 24" x 12"
COMPLETE SYSTEM
/1150.L55
308" x 281" x 12"
425.96
Inrl. 2 Spotbanks and bulbs.
MAIL ORDERS & EXPORT INQUIRIES TO:Barclaycard
AUDIO ROUSE, BEEOONNIB LANE. LEEDS, 19.
and Access
accepted
All items subject to availability.
Prices correct at 5.3.76 E. & O.E.
EDINBURGH 101 Lothian Rd. (Cl. Wed.).Te1. 229 9501
GLASGOW 326 Argyle St. (CI'd Tues.). Tel. 24$ 4155
HULL 7 Whltefriargate (Closed Thurs.). Tel. 20505
LEICESTER 32 Mph Street (Closed Thurs.).Tel. 56420
LEEDS 5-7 County (Maces) Arcade, Brlggste
(Closed
ed. Tel. 453252
LIVERPOOL 35 Dawson's
St. John's Shopping
Centre (Closed Wed.).
LONDON 235 Edgware Road, W.2. (Closed Thurs.).
Tel. 723 1529
MANCHESTER MA Oldham Street (Closed Wed.).
Tel. 23e 2775
MIDDLESSROUGH 103 Linthorpe Rd. Tel. 210585
(Closed Wed.)
Te : Pudsey 106799) 77691.
MAIL ORDERS MUST NOT BE SENT TO SHOPS
TERMS O.W.O. er 0.0.0. No O.O.D. cadet 11.
POSTAGE 40p PER ORDER OR AS QUOTED.
TRADE SUPPLIED.
LARGE B.A.E. REQUIRED
NEWCASTLEUPONTYNE
24 Newoate Shopping
Centre 59 Grainger St. (Cloud Wed.). Tel. 21467
NOTTINGHAM 19/19A Market Street
(Closed Thurs.). Tel. 480M
PRESTON
41 Frlargate Walk. St. Georges Shoppo Prec. Tel. 51979
SHEFFIELD 13 Exchange Street (Castle Mkt. Bids.)
(Closed Thum.). Tel. 20719
STOCKPORT
9 Little Underbank (Closed Thurs.). Tel. 480-0777
SUNDERLAND B Market Sq. (Closed Wed.). Tel. 70679
YORK
5 CHURCH ST.
(;s6)
Tel. 34355
3
vac
TRANSISTOR UNIVERSAL AMPLIFICATION CO. LTD.
163 MITCHAM RD. LONDON SW17 9PG 01- 6723137/9080
MONO DISCO MIXER WITH AUTO FADE
TUAC
Designed for the discerning D.J. of professional standard.
Offering a vast variety of functions. Controls: Mic Vol; Tone,
over -ride depth, auto /Manual Sw; Tape Vol; L & R Deck
Faders; Deck Volume; Treble and Bass; H. Phon Vol Selector;
Master Vol on /Off Sw. Max output 1V RMS.
Specification: Deck Inputs -5OmV into 1MC1; Deck Tone Controls-treble +20 -1OdB at 12kHz, Bass +22 -15dB at 4OHz;
Mic Input-200 ohms upwards, 2mV into 10kí2; Mic Tone
Control -Total Variation Treble 15dß, Total Variation Bass
1OdB; Tape Input-3OmV into 47kÁ; Power Requirements
30-50 volts at 5OmA.
-
*
PANEL SIZE
18
x44in.
DEPTH Sin.
TUAC AMPLIFIER MODULES
*
PRE AMPLIFIERS
VA08
Designed for use with TUAC power amplifier modules. Extensive research has gone
into various wide range tone control circuits
to produce superb sound quality. Thousands are already in use In high quality
professional amplification systems.
VAO8 Vol. Treb, Mid and Bass controls.
HI. IMP. FET. I/P suitable Mid. Guitar,
Radio, Crystal /Ceramic P.U. Sensitivity
4mV. Treble +35dB at 16kHz. Mid +20
-15dB at 1kHz Bass +20 -10dB at 4OHz.
£8.50
VAO6 Vol, Treb, and Bass controls. Sensitivity 8mV. Treb +28 -15dB at 12kHz,
£5.50
Bass +18dB at 40 Hz.
SVAO8 STEREO PRE AMP Vol, Treb, Mid
Guitar,
I/P
suitable,
and Bass controls,
Radio, Crystal/Ceramic P.U. Sensitivity
4mV. Treble +35dB at 16kHz. Mid +20
-15dB at 4kHz. Bass +20 -1OdB at 4OHz
Plus Full Balance Control. Full I/C operation
£12.50
supply voltage + 15VDC..
POWER AND QUALITY
Power supplies vacuum impregnated.
Transformers with supply board
incorporating pre -amp supply.
125 watts RMS
continuous sine
wave output
TLI00
TL60
5x5x3in.
IE
19.50
PS 450 for supplying
TL60s
Rugged layer wound driver transformer
Short- Open -and Thermal overload
protection
Only 6 connections
2
£22.00
£19.50
£5.50
85/87
Hurst
Street, Birmingham
(Tel. 021 -622 1941)
Arthur. Sallis Ltd., 28.Gardner St. (Tel. Brighton 65806),.
Bristol Disco Centre, 26 The Promenade, Gloucester
Road (Tel. Bristol 41666)
Socodi, 9 The Friars (Tel. Canterbury 60948)
Cookies, Disco Centre, 132 West St. (Tel. Crewe 4739)
Al Music Centre, 88 Oxford. Street, Manchester
(Tel. 061 -236 0340)
Damon Electronics, 99 Carrington Street (Tel. Nottingham 53880)
Electra Centre, 58 Lancaster Road (Tel. Preston 58488).
Mitchell Electronics, 64 Winchester Street (Tel.
Salisbury 23689)
Mitchell Electronics for Southampton area
.
.
RMS
2 R.C.A. 150
15
watt
amp transistors
£16.25
£13.50
2
PS 125 + 45 volts for TP125 £1375
PS 100 ± 43 volts for TL1O0 £12.00
PS 80 ± 38 volts for TL6O
£11.50
PS 30 ± 25 volts for TL3O
£750
PSU 2 for supplying disco mixer
STOCKISTS--CALLERS ONLY
watts
wave output
wave output
2 R.C.A. 110 watt
IS amp transistors
TP125s
PS 80/80 for supplying
Matthews,
100
continuous sine
continuous sine
R.C.A. 150 watt 15 amp output transistors
Geo.
Sx5x3in
60 watts RMS
TPI25
7x6}x3in
4
*
Specification on all power modules. All output
power ratings ± O.5dB; Output impedance 8 -15
ohms; THD at full power 2% typically 1 %;
input sensitivity 60mV into 1OkC1; Frequency
response 20Hz -20kHz +2dB; Hum and noise
better than -70dB.
TL30
pled power amplifier
coupled
module.
E
D.C.
RMS
WAVEE
CONTINUOUS SI
OUTPUT IMPEDANCE 8-15 OHMS
T.H.D. AT FULL POWER 0.5%
SIGNAL TO NOISE RATIO -8588
INPUT SENSITIVITY EOmV INTO 501( OHMS
FREQUENCY RESPONSE 25Hz -50kHz
8 TRANSISTORS
4 DIODES
ONLY SIX CONNECTIONS
Send large stamped addressed envelope with all enquiries or send £1
(refundable against purchase) for fully illustrated 20 page catalogue.
4
Practical Wireless, May 1976
FUZZ LIGHTS
TUAC
,h,
r,"nv..'
.,
.
.
! ,ON1C AN:, AMP. fICA- :pN
Ei%ulPMlN
,_r :_
-
Pi NtiOtvAL SHOPPCf, S,MON
'
5
'fli:,
.
p:f', an;1 SAT
TUAC STEREO DISCO MIXER
RED
GREEN
AMBER
BLUE
volt a.c. Long Life Candle
Bulb, Revolving Reflector, adds a
new dimension to disco lighting
effects.
240
INPUTS. Four identical stereo inputs available with any equalisation. Two magnetic and two flat supplied as
standard. High quality slider control on each channel. Volume treble, and 'asas contols for each pair of
sliders. Sensitivity mag., 3mV (R.I.A.A. comp.). Flat 50mV at 1kHz. Bass controls ± 13dB at 60Hz. Treble
controls
f
A
18dB at 15kHz.
E/
J
C
3 volts (+12dB) available. Attenuated output for TUAC Power
Modules. Rotary Master and Balance controls. Band width 15Hz -25kHz }_1dB.
P.F.L. Output 250mV into 8 ohms. Rotary Volume Control. Monitoring facility for
Size: 25in long
all 4 channels. Selection via touch sensitive illuminated switches. Switched visual
61n high x 31n deep
cue indicator.
MISCELLANEOUS FACILITIES. Two Illuminated deck on/off switches. Mains ilium. nated on /oft switch.
Auto fade Illuminated on /off switch. Mains powered with Integral screen and back covet. Complete with full
OUTPUTS. Up to
instructions.
*
*
*
*
Output power 60 watts R.M.S. Four
Inputs, two channels each with
vollumo, treble, middle and bass
controls. Variable waveform control
Lo-Line Twin 125
(125 watts version)
Lo -Line 60
£9800
(single pre -amp version)
Lo -Line 125
(single pre -amp version)
Lo -Line 125
slave output power,125 watts R.M.S.
£81.00
AY
All
Lo -Line
Amplifiers are 251in long x
Min
high
£6500
£70.00
x
61in deep
AY
NEW TUAC LO -LINE STEREO 250 125 WATTS PER CHANNEL
4 CHANNEL SOUND TO LIGHT
3 CHANNEL LIGHT
SEQUENCE CHASER -4LSMI
MODULATOR
RCA 8A Triacs
1000W per channel
Each channel fully
suppressed and
fused
Master control to
operate from 1W to
RCA 8A Triacs
1000W per channel
Fully suppressed and fused
Switched master control for
sound operation from ;W to
25W
Speed control for flied rats
sequence from 8 per minute to
50 per second
Full logic Integrated circuitry
isolation for
with
op ",Ica!
amplifier (protection
Full wave control
100W
Full wave control
12 easy connections
£15.50
'.3 easy
(Single Channel Version 1500 Watts £725)
ADD SEQUENCE CHASING AND DIMMING EFFECTS
TO YOUR TUAC 3 CHANNEL LIGHT MODULATOR
connections
Patents applied for
£17.25
HOW TO ORDER BY POST
Make cheques/P.0.s payable to
Speed Control 3 per
min. to 10 per sec.
Fuli logic integrated
circuitry
Dimmer control to
each channel
9 easy connections
SEQUENCE DIMMER MODULE -3SDMI
£11.75
TUAC LTD(PWS)
'
or quote Access /Barclay Card No
and post tá TUAC LTD [PM)
163 Mitcham Rcád, London, SW17 9PG
We accept phone orders against
Access /Barclay Card HDIders
Phone: 01 -672 3137/9080
ALL PRICES INCLUDE V.A.T. POSTAGE AND PACKING FREE
ACCESS
&
BARCLAY CARDS ACCEPTED JUST SEND OR PHONE US YOUR NUMBER. H.P. ENQUIRIES INVITED
Practical Wireless, May 1976
5
P & P. EXCEPT f WHERE
ACCORDING TO WEIGHT & DISTANCE -BRS.
Wide range of Audio accessories & semiconductors.
CALLERS WELCOME (MON. -FRI.)
SWITCHES
50 VOLT RANGE
L1.06 OR SEND FOR LISTS.
SPST TOGGLE 3 FOR
Prim. 200 -240V
NO HIDDEN EXTRAS -Prices include VAT and
TRANSFORMERS
-SAME
DAY DESPATCH
ALL EX- STOCK
and or 24 Volt
PRIMARY 240 -250 VOLTS
MAINS
ISOLATING
12
PRI. 120/240V
SEC. 120 /240
Ref.
07
Ref.
TAP WITH
CENTRE
SCREEN
213
VA
71
(Watts)
£
3.97
5.84
6.67
20
60
49
50
100
10-43
200
250
350
500
750
1000
51
52
53
54
55
56
57
58
1267
14.99
17 21
23.69[
33-017
1500
37.681
42 03t
2000
66.407
59
3000
115V or 240V Sec.
only.
Prim. 200 -240V
Sec. 0- 12- 15- 20- 24-30V
Amps
C
Ref.
258
0.5
112
2.0
3.0
4.0
5.0
6.0
8.0
3
20
21
51
117
88
89
60
3.38
4.85
5.99
1.0
79
6.92
8.32
9.33
12.38
10.0
12 71
VOLT RANGE
Amps
124
126
127
I.0
2.0
C
3.46
4.75
6.67
9.58
0.5
3.0
4.0
5.0
6.0
8.0
I25
123
40
120
121
122
189
II-45
I2.41
14.56
17.011
20.951
IO -O
21877
12.0
2
1.97
2.64
2.80
4.60
I
68
3
-
18
4
2
5
-
398
85
70
5'36
6
3
108
8
4
72
10
12
16
5
6
Sec. 0- 19- 25- 33- 40 -50V
Ref.
Amps
L
No.
102
3.46
L
0.5
1.0
6.41
4.61
20
104
105
106
107
118
119
4.91
6-26
7.63
9.83
3.0
4.0
6.0
8.0
15.08
16.46
TRANSISTORS
AD161
AD182
AF114
AF115
AF118
AF117
AF118
AF124
AF126
AF126
42
AFI39
20
80
20
86
80
17
84
87
80
80
A8Y26
ABY27
A8Y28
ABY29
ABY67
BA146
BA164
HAM
BAX12
BAX13
BAXIB
BC107
BC107A
24 BC108
24 BC108B
48
24
24
47
80
80
88
34
60
37
BC109
BC109B
BC109C
BC116
BC116
BC117
BC118
CI .06
15W 43.17 I8W 42.92
L2.71 SOLDERING IRON
COMPONENT PAKS
STAND
14'17
200 Mixed value resistors (count by
150 Mixed value capacitors (count by
l
30 Mixedd value
precision resistors
15 Assorted pots & pre -sets
10 Reed switches
2'..
KIT
ABOVE
FOR
LI.49
MAGNETIC TO CERAMIC
CARTRIDGE CONVERTOR
VOLTAGE
I
3
30
84
80
84
70
15
10
18
10
4
8
11
12
10
11
11
12
10
16
16
18
10
28
14
}w 2%
Micro Switches
20 Assorted tag strips & panels
I
I
100/120
236 200, 200
200/240
or
1'95
0 -15, 0 -15
I
on
off switch, neon Ind. Stereo
headphone socket. Plus Instructions book L35.53.
1
CASED AUTO TRANSFORMERS TEST METERS
mains lead input & USA 2 pin AVO 8 MK5
161 '54
AVO 72
42424
Ref 113W
L4.33
AVO TT 169
124.54
150VA
17.80
Ref 4W
AVO
Cases and
AVO
Ref 67W
SOOVA
413.37
Accessories.
Ref 84W
I000VA.
L19.86í
Ref 95W
2000VA
431 001t
POWER UNIT
ON SITE TOOL ISOLATORS CC12 -05 Output Switched
240 to 110V -500VA to 2KVA
3- 4.5- 6- 7.5
12V
(to 853535) Send for details
at500mA. (4.92.
240V
outlets.
20VA
4
-9-
BC132
BC136
BC136
BC137
BC138
BC139
BC142
BC143
BC147A
1111C178B
18
BV16IA
12BC179B
19
BC262A
18BC182B 10 BC266A
18BC182L 11 BC287A
16BC183B 10 BC268B
86BC183L 10 BC289
82BC184B 12 BC287
24BC184L 11 BC300
9BC186
25
SAE FOR LISTS
& GIFT SIL 108
Plastic BC 108
while stocks last
BC157B
BCI58A
BC169A
BC167A
BC168B
BC171A
BC172A
BC173B
BC301
BC302
BC303
BC304
BC307A
BC308A
BC309B
BC317A
12BC212A 18 BC319B
18BC212L 16 BC322B
18B0213B 12 BC327
11BC213L 14 BC328
14BC214 15 BC337
11BC214L 17 BC338'
16BC237A 18 BC461
15 BC667
ienC?óuR
BC668
D
18
16
18
14
18
18
80
87
28
24
30
27
16
14
18
12
18
16
20
18
18
16
36
9
D
BC559
9
BCY70
BCY71
BCY72
BD116
BD121
BD128
BD124
BD131
BD132
BD133
BD136"
15
18
14
80
90
90
68
36
38
65
87
39
44
47
64
76
84
70
80
22
20
20
26
80
BD136
BD137
BD138
BD139
BDI66
BD166
BD232
BDY20
BF116
BF164
BF158
15V, 18V, 30V.
All at 12p each
VAT -Items marked
15V
a
IA
173p
TIL209 Red
Pre -selected
CARTRIDGES
Magnetic Sonotone 100
Ceramic E.E.I.CS 2000
L5.85
¿1.95
TEAK AUDIO KIT 25W
Teak veneered cabinet
161:
+II }: }31:,
Iuminium
heat sink and front
panel brackets plus back panel
and sockets etc. L12-16
chassis,
STEREO FM TUNER
stations supply 20 -35V. 90mA
Max
L25.20
Barrie Electronics Ltd.
3,
THE MINORIES, LONDON EC3N 1BJ
TELEPHONE: 01-488 331611/8
NEAREST TUBE STATIONS: ALDGATE
&
LIVERPOOL ST
A hobby that
pays big salaries.
Enrol in the BNR & E School and you'll have an entertaining
and fascinating hobby. Stick with it and the opportunities
and the big money await you, if qualified, in every field of
Electronics today. We offer the finest home study training for
all subjects in radio, television, etc., especially for the CITY
AND GUILDS EXAMS (Technicians' Certificates); the Grad.
Brit. I.E.R. Exam; the RADIO AMATEUR'S LICENCE;
P.M.G. Certificates; the R.T.E.B. Servicing Certificates; etc.
Also courses in Television; Transistors; Radar; Computers;
Servo -mechanisms; Mathematics and Practical Transistor
Radio course with equipment. We have OVER 20 YEARS'
experience in teaching radio subjects and an unbroken record
of exam successes. We are the only privately run British home
study College specialising in electronics subjects only.
Fullest details will be gladly sent without any obligation.
g im
1.1
I BRITISH
EN EN
ise
im mi
imp
NATIONAL RADIO
am we
& ELECTRONICS,
SCHOOL, Dept WC56
P.O. Box 156, Jersey, Channel Islands.
I NAME
85P
ADDRESS
add 25 %, Rest at 8%
Flint House, High Street, Wallingford, Oxon OX10 ODE
Telex 4SPWALFRD849343/
\Lel. Wallingford (0491) 35529
6
El -30
POWER SUPPLIES 3 -5 -IOW LI .68
0-20
P & P
POWER SUPPLIES 25W
[3 93
2dß TRANSFORMER
.
(DC) 20-12-0-12-20
214 7
VA
Ref.
C
3W
12.42
0.15 -20, O -IS -20 4 70 TRANSFORMER 5 -IOW
5 77
206 IA, IA
60
243
£3 08
13 33
203 500, 500 O- IS -27, O -IS -27 4 18 TRANSFORMER 25W
350
247
£3 95
0.15
-27
5-14
t
015
-27,
IA,
IA
1000
250
28 4I
204
12, 15, 20, 24, 30 2.68 8Sß MINI -DECK
47 65t 5112 500
2000
252
4 Speed Auto Changer
18.28
BRIDGE RECTIFIERS
AUTO TRANSFORMERS
Auto Tops
Ref VA
0-60 BSR PI28R
2A
50V
£
(Wottsl
0-66 Single and Auto (Chassis) L21-38
100V
2A
G
d SPIS (Chassis) L22.58
2.44
113
20 0 -115- 210 -240
I -03.
6A
IOOV
4.07
75
64
IA
0.60 NEW STEREO 30
200V
4
150 0 -115- 200.220 -240 5.45
0.72
2A
200V
Complete
Stereo Chassis inc.:
7 -S1
66 300
..
..
0.78 7í7w RMS, Amp, Pre -amp,
2A
146 400V
67 500
400V
4A
0.97 Power Supply, Front Panel,
1715
84 1000
2A
0.85 Knobs (only needs Mains Trans.).
600V
20-541
93 1500
0.97 Stereo 30 L19-94. Mains Trans
2A
27-447 1000V
95 2000
39461" 500V 10A(PM 7A6) 2.71 13.41. Teak veneered cab. L4-87.
73 3000
Sec.
}p
80p
FOR
FOR
I
BF159
BC119
AF188
9 BF160
AF299
BC125
RESISTORS
SILICON
INTEGRATED
each
RECTIFIERS
1
CIRCUITS
SAE for full 1st of com60V 3A
lap } watt 512 TTL
ponents "same day de100V 3A
15p range
DIGITAL
200V 9A
mail order
spatch to
18p 111 -10m n
7400
18p
"Minimum
THYRIETORB
customers"
7401
20p
100V lA
DIODES
80p
order &l p & p 25p ".
18p
7402
6p
200V IA
40p IN4002
18p
Callers Mon. -Sat. Incl.
600V IA
IN4006
7403
10p
BT 106 120p IN4148
7404
6p
23p
ZENERS (400mul
INTEGRATED
VOLTAGE
LED
52X03fBCY88
125R Red 20p
CIRCUITS
REGULATORS
3V3, 3V6, 3V9,
125A Amber
(T03)
LINEAR
4V3, 4V7, 6V1,
ß7P
6V6, 6V2, 6V6,
5V 1A
175p
709 (8 pin Dil) 40p
126Y Yellow
7V6, 8V2, 9V1,
ß7p
10V, 12V, 13V,
12V 1.0
173p
741 (8 pin Dill 83p
NE555
3
6
10.0
BI-113i11113%
20
SLIDE
ANTEXSOLDERINGIRONS
20 -45V
OPERATING
ALL AT 95p PER PACK.
1917} ONLY 43.51.
116
MINIATURES
SCREENED
HIGH
QUALITY
MODULES
9 13
AUDIO KIT 25W
17
8
£
Ref
Volts
mA
10
3 Watt RMS AMPLIFIER
L3.06 2í25W Amplifiers
115 20
16 86
1.98
238 200
3-0-3
5 Watt RMS AMPLIFIER
£3.50
187
0
16 86
30
2.71 10 Watt RMS AMPLIFIER [3.86 14 Pre -Amp
0 -6, 0 -6
226 60
30
19.08t 212 IA, IA
1.96 25 Watt RMS AMPLIFIER L5.13
9 -0.9
13 100
+Power supply
2.04 125W RMS AMPLIFIER
235 330, 330 0 -9, 0 -9
+Transformer
HIGH VOLTAGE
L17.41
2.73 PRE-AMP for 3 -5 -10W
207 500, 500 0 -8 -9, 0 -8 -9
Mains Isolating
+Front Panel
18.30
3.94 PRE -AMP for 3 -5 -25W
0 -8 -9, 08 -9
Prim. 200/220 or 400/4401208 IA, IA
L17.05
I. Kit of parts to include
6.86
7-42
rcharj
AC126
AC126
AC127
AC128
AC132
AC141
AC142
AC161
AC153
AC176
AC188
TOGGLE
DPDT
DPDT
I
Prim. 200 -240V
Sec. 0.24-30-40-48-60V
Ref
Ami,,
0.25
1.0
0-5
12v
BE
0
VOLT RANGE
30
III
CARRIAGE WILL
1
amnion=
- - - -IN
'
(Block caps please)
sommismosi----
Practical Wireless, May 1976
wiiiruiuii
SAXON
ENTERTAINMENTS LTD
professional standards realistic prices
.
SAI208D -120 WATTS RMS POWER AMP
Uses 150W I6A RCA devices
-
All three types include
,,.
Transistors 4 Diodes -Fibre Glass P.C.B.
%: Noise-80dB
Typical Distortion
Short, Open Circuit proof-Load line limiting
Only FOUR Connections- Simplicity!
High sensitivity (240mV) suits most mixers
1dB Frequency response
30 Hz-40kHz
Singlesupplyline- nooutputcapacitorneeded(95v)
Standard 852 output-will operate on other
impedances
x 3" x 14" (15 x 8 x 4cm)
Compact
All individually tested before despatch
All units individually tested and guaranteed
10
POWER
SUPPLIES
~"'.
-04
-
*
i
-6
SA 1208D L19-50
SYSTEM 7000 -DISCO CONTROL
¡
t
Tough, bold, two tone stainless panelfor panel mounting or freestanding
u
for
2
cartridges/tape/
Inputs
ceramic
L
microphone
Individual deck controls AND left /right
fader
Low noise (- -80dB) 20 Hz-50kHz 3. 1dB
Suits all Saxon amplifiers and most other
t'
-(
--
*
-
MONO
--
for two
£1530
SYSTEM 7000 MODULAR MIXING
COMPLETELY WIRED WITH STAINLESS PANEL
Up to 20 channels mono, stereo or mixed
Inputs for all sources inc. mag. cartridge
0
i
Soundlite
3kw Converter
Module
'--
1 kW /channel:
individual tone and master controls: RCA BA
triacs: Scintillating Light
Dispay: Operates from
any amplifier: Glass -fibre
°
_
a
O/P up to
"
PCB: Unbeatable value
at
On P.C.B. requires only plug/socket/
panel for mounting as desired £2775
t
'
ri.
,i!
®y.
£8.50
With same facilities and
performance as complete
units with panels as
t7t
illustrated. Up to
input modules may be
used with one mixer. On
V.
Individual monitor buttons
glass
.
l
IM.7001/M
input
Imo 70ói%5
stereo input
IM.7002 /M
Il.. GO
mono mixing
IM.7002/S
stereo mixing
Giant
Complete with wheel
Wide range of extra effects mar
Cabinets
post- Please make
be
attached
Sturdy
construction
Adjustable feet
Spare wheels
8 %.
£29.20
£490
Attractive range of speaker and other cabinets
at our showrooms. Enquiries welcomed.
PRICES include carr.:and packing. VAT must be added to all orders at
r
150 watt tungsten Iamb
'>
327 -333
£550
£9 00
£5.50
£9.00
Yf
!`
_..
C.O.D. 65p extra: S.A.E. all enquiries please.
cheques or crossed P.O.'s payable to
WHITEHORSE ROAD, CROYDON, SURREY CR0 2HS
6846385.'0098
Telephone: 01Shop Hours Siam-5pm (Lunch 12.30 -1.30): Sat. 9.30am -5pm. Prices and specifications
sjhject to alteration without notice.
Mail Order desk l0am -4pm Mon -Fri.
VAT NO.
Practical Wireless, May 1976
edge
ACCESSORIES
Mies: Headphones: Special Lamps.
SAXON ENTERTAINMENTS LTD.
ACCESS or
or
connections.
150
1
-fibre PCB's.
Soldered
,
WATT LIQUID
WHEEL PROJECTOR
SAXON STROBES
NUPERSTROBE
flash /2 sec up to 20 flashes /sec
L24.75
Compact black Bondene case
Ideal for the mobile disco or smaller club
l'RO-STROBE
External trigger-audio up to 240V
Use with Soundlite for rainbow strobe effect
Smart, tough Bondene case Bin ;: tin
5in.
80 watt tube Discharge
ß8.5O
energy up to 6 Joules
£ 15 50
IN PCB
MODULAR FORM
nm
i
£27 50
50
FRONTPANEL £3.50
FoR ABOVE
0--
-'
-" -- satn
Stereo £1200
Orders by
f 18
SUPERFECT MODULE
with Panels
as illustrated
MIXER Mono
subcircuit
of disco
plugs, socket and one
switch required.
STEREO
MONO
STEREO £49.50
Only one mixing module required
most amplifiers
P
IdB
20Hz -30kHz
Complete -ready to plug in or solder
12'/50W high grade chassis units:
Loudspeakers
P
14000 gauss: presence dome: £14.50
Form
Printed
control unit: All electronics included. Only
,p,
£38.00
Inc. case and plug -ready to use
£8.50
In Modular
assembly version
._-o
Full control of 3kW of lights (IkW /channel)
Audio control plus sequence plus override
Variable speed sequence with slider function control
Stainless steel two tone panel- matches mixer
13 transistors 8 diodes -advanced control circuitry
High audio sensitivity-operates from any amplifier
Attractive Bondene case -free standing or panel mounting
Individual tone controls plus master audio control
Stereo 112-00
PM301/2 for one or
£8.80
two SA308
h
-
Wide range bass and treble controls
}W monitor Ppower outlet
Modern low noise circuitry
Echo send /return facility
5cm matrix -bold panel
Send for details
PM601/2 for one or
two SA608 £10.50
(48V)
812
°-
£34.50
CONTROL UNIT
message on our answerphone.
PM1202
SA1208D
Sim
SYSTEM 7000 LIGHTING
BARCLAYCARD
No. for prompt attention.
After 5.0 p.m. leave your
for one
£11.60
-L. to R.: Mic, Vol /Treble/Bass,
Autofade depth, L/Deck Vol, R /Deck
Volume, Tape Volume, Treble, Bass.
Master, Monitor Volume, Monitor
Selector -On -Off
watt headphone monitor -five position
switch with mute positions
Send or phone your
PM120/1
SA 1208
Controls
makes
\fïl
and ready to wire:
£9.50
'
f
í}ï
W. RMS
into 812 (65V)
£ 12.50
into
UNIT
F.,
Wr7
high grade transformer, fully fused
Large SAE brings leaflet
¡
INPUT Mono
SA608
SA308
30W. RMS
a
Ae1
''_/
Complete and ready to plug in
Totally encased -no soldering at all
on glass -fibre P.C.B.,
60
-$
,.(
AI
In the
same series
218 6921 49
TRADE
ENQUIRIES
Send for name andaddre.+.v
of your nearest wholesale
supplier.
RGD ENGLAND 1091983
7
©
0
E
DIGITAL
"ALPHA ":
Alpha
Alpha
Alpha
Alpha
CLOCKS
:
4 GREEN
5"
O
:
KITS
HIGH DIGITS
Module (excl. case)
Module (excl. case)
complete: Perspex Case
Clock: Perspex Case
u
T
Alarm
Kit
Built
Kit
Built
CALCULATORS
£900
m
AM/PM
Mains failure Ind.
Tilt Snooze
Auto -Control Brightness by Photocell
ALARM
:
Module kits
Std.
10.00
11.00
12.50
17.50
13.00
14.00
15.50
21.50
S
INCLUDING VAT, P. AND P.
SATISFACTION GUARANTEED
MIN
"DELTA ":
Delta
Delta
Delta
Delta
Delta
Delta
S
4 RED
5"
HIGH LEDs
Alarm
Module (excl. case)
Module (excl. case)
complete: Perspex Case
Clock: Perspex Case
complete: Teak Case
Clock: Teak Case
-
Kit
Built
Kit
Built
Kit
Built
Modern 2 Part Case
Drilled P.C.B.
4 Digit Display (:!5 inch high
All components included
Even Mains lead included
Full instructions
Assembly Drawing
Circuit Diagram
Std.
9.00
9.50
12.00
17.00
12.70
17.70
11.00
11.50
15.00
21.00
15.70
21.70
-
Perspex Case Colours: Black, White, Red, Green, Blue, Orange
Built Modules and Clocks: state 12 or 24 hour (Delta 12hr only).
Complete Clocks: 2 Year Guarantee
plpl
"NOVUS" CALCULATORS
850 Mathbox
650 Mathbox ....£540
6020
4510 Mathematician .. £16.20
C.W.O. PULSE ELECTRONICS (PW12),
©
plplp>.
plplplpr\
El
III
131
You supply only mains plug
Easy!
and standard tools
-
.... £6.75
Statistician .. £21.60
202
Shefford Road, Clifton, Shefford, Beds. SAE complete range
Q-_ 0_-13
8
ACOUSTIC
CORPORATION LT D.
B ENTLEY
©
;
UM
Q6156/3i$R
0-©
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2Y
VH1Ó:
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PÑÚlÓ6
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110 ACY28
18 BYZ11 88
ECH42 80 EY84
92 PCF201 1 06 QV06/20
340 V0120 1.17 AD140 97 BY212 33
ECH81 40 EY86/7 40 PCF801 666
AD149 64 BYZ18 .83
.76 VU120A
5CH83 .52 &Y88
60 POF802 .60 R19
FSY1IA 29
1.17 AD761
59
ECH84 .60 5Y91
-20 PCFB06 .60 T11233 100
AD162 59 FSY41A 19
7a GLOUCESTER ROAD, LITTLSNAMTON, SUSSEX
ECL80 40 2240
TP2620100 VU183 80
55 P033200
AF114
.18
75
88 OA9
46 5241
.66
UABC80 47 W107
Telephone 4743 ECL82
All prices Inclusive of V.A.T. at 13%
30 OA10
66
ECL88 .88 5280
36 PCL82 45 17AF42 76 W729 117 AF116
X86
AF1I7
0A47
18
P0L83
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so
16
1-49
ECL84
5281
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DF91
30
36
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351 35A3
OB2
.46 6BA6
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AF121
39
0A70
20
UBC81 80 2759
40 6K8G
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.66 EC1.85 70 GY601 .82 PCL84
53 12J7GT 70 3606
0Z4
66 6BC8
PCL86
AF124
0A78
20
Tremblers
83
'56 UBF80 47
.47 0232
.69
-41 611 ' 2 34 12K5
117 35D6
1A3
10 DK40 -Y ECL86
86 6BE6
AF125 12
0A79
12
1.00 0233 1 46 PCL805 '70 UBF89 47 R Diodes
68 12K7GT $0 35L60T 48 DK92 116 EF22
.76 81.66C
1A60T 49 6B116
23
AF326
0481
12
PEN45
1.00
154744
18
90
EF40
0234
18
-00
.86 35W4
.60 DK96
64 617
59 12K8
UBL2l $ $4 2N404 88 AF180 82 0485
1A7GT .60 BBJB
12
82 07.37 110 PEN45DD
04 EF41
64 12Q70T 60 3523
18 DL96
1B80T 68 6BK7A .86 6L18
$O 25966
110
AF186
.71
0A90
16
6$
HABC80
50 35Z40T 69 DM70 80 EF42
UC004
1H60T 80 6BQ7A .64 6L19 2 00 128C7
90
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80 PEN46 00 UOCB6 N 2N1766 64 BAllb 18 0491
115
114
95 61157 110 8LD20 88 12807 55 80260T 90 D1971 176 ET"
BA116
12
P5N453DD
2N2147110
13
0495
EF80
.80
HL28DD
100 DY87/6 41 EF83 146
1N66T .76 6BR8 1'25 6N7GT 70 12857 50 42
90 2N2297
BA129 18 0044
18
8,00 IICF80
80
0C1121 2
1.64 8Q70
60 12637 60 43
156
.50 6B87
1-00 DY802 47
BA180
0045
PENDD
252369
14
13
18
40 HL41DD
6Q70T 60 128Q7 .76 00B6 100 E80CC 867 EF85
UCH42
184
$9 6BW6 100
8$
4020 1.00
90
253053 42 BA163 10 0C48
.70 E807 ß80
lU4
70 6BW7 .86 8Q7fM) N 128RT 75 6006
PFL200 8$ UCH81 47 2N3121 588 BC707 16 0070
16
86 HL42DD
E88fX; 110 F89
70 1457
1U6
47 6ß7G
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18 6826
PL33
14
60 UCL82 '46 2N3703 25 BO108 16 0071
2021
47 BSA7
66 1987
110
148 E92CC '70 EF92
-00 6C4
UOLB3
64
14
50109
10
0072
253709
16
PLSB
40 HN309 176 pm,
70
19086 .66 605H6 88 E1807 117 5F97
20K6 .76 6050
69 68C7GT
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89
BC118
0074
M
AA119 20
ß8
94 HVR2 100
2X2
.47 6807
62 1906 710 60160T1.00 B18200800 EF98
70 606
UF42
-68 A4120
BC116
0076
14
10
10
HVB2A
95
PL81A
60
6827
'40
15
20D1
86A2
76
51148
3A4
.60 609
800
80
41 AA129 20 BC116 33 0076
.4$ IIF80
20
EF183 -40
117 PL82
29
0077
$6
AAZ13 18 50118
.40 KT41 117 PL88
60 UF89
DF86
119 90AG 893 5A76 140 EF184
3Q4
3D4
86 6CD8G 180 68K7OT 58 20L1
i7
BCY10
0078
$0
69
50 UL41 76 A0107 90
176 KT86 ßS8 P1A4
.60 20P1
8$ EABC80 46 EF804
3Q6GT .79 8C08A -86 68Q7
100 9001
BOT12 64
0078D
AC11S
E590
KT81
P1604/600
d4
&1p
EAC91
.66
6018
6V611
90
20P3
9000
981
384
47
74
W
UL84
.4p AC126
BCY33 18 0081
14
16
EL32
00
KT88
6'76
088
88
354
68 60L8A 84 6VBGT
2054
117 160B2 160 EAF42
IIMBO
60 AC127 88 BCY84 29 0081D 14
4058
76 60M7
Ba 6X4
.47 20P6
1.60 21580 10 &AF801 40 5L34 100 KTW81176 PL606 115 UY41
44
50 AC128 16 5CY38 29 0082
88 8X6GT 40 25460 .70 807
1-17 5534
.85 EL36 800 KTW82178 P1408 110 13Y86
6008
75 6C176
00 AC132 46 BF168 18 0082D 14
.28 EL37
1100 KTW83117 PL509 116
6R4GY .94 6CW4 117 756
88 261.60 70 5702
110 E591
OC88
841
A0164
18
II10
117
.38
57169
E141
10
MHLDB
PY39/2
10
5U40
50 8D3
-76 7B7
18 26Y60 40 5768 176 E5041 -88 EL81
AC166
2e BF163 18 0084
41
70
100 PY80
47 1312/14117
5V4G
46 26Z4G 60 6057 100 5BC81 46 EL83
88 7117
66 8057
73
49
00128
49
4.00 AC157 88 137173
.70 P61
80 PY81
40 1319
5Y3GT 56 BDTBA 18 7R7
.76 8080
810 2526
100 E8780 40 RL84
70 AC386 .88 5F180 89 00169 19
46 PABC80 46 pY82
49 U26
S29
BO 25160
10 8067 110 &BF88 60 5L86
88 6EN8 .p 7Y4
00172
46
AC166
57181
52
U26
98
65
5C813
70
60
py88
86
-80 28D7
18 55789 40 5L95
5240
56 6E5
117 7Z4
2.00 7193
0C200
60
62
70 PC88
70 Py88
1.76 AC168 49 BF185
47 U88
62441T 55 8F1
80 9D7
/0 30A6 76 9002
.69 EBL21 584
19 00201 M
70 PY600A
U86
175 AC178 71 BFY60
8/80L2 .80 8780
76 80015 80 9008
60 5C86
.90 5L380 1.80 P095
10 1002
AC177
80 131,561 15 0C202 15
42
U45
120
1.17
1.11
EC88
90
6A80 240 6F13
10D57
88
ACPEN
117
ELM
2C97
30017
10
16
18 BFY62 16 00203 >o
88 PC900 10 PY800 46 1781
-68 EM80
80 ACY37
10 6F14
8AC7
88 80C18
86 AC2/PEN/ EC92
88 IOFI
86 BY100 28 0C204 49
76 PCC84 40 PY80I 45 0191
$0 ACY18
6AG6
16 8715
76 3075
DD 1.00 ECM 9.00 EM81
.76 1079
76
18 áC206 66
'84 PCC86 50 P230
94 ACY19 $6 BY114
-60 U261
BAHR
80 6F18
84 10718 60 SOFIA 110 ACBPEN 60 ECC36 200 EM88
17 PCC88 66 QQV03/10
U801
86 ACY20 $8 BY126 20 00208 117
51x40 110 5M84
6AJ6
.76 6F23
SO lOLD11 12 30FL'2 110 AC/TH1
PCC89
EM86
110
40
210
6AK6
1-00 ECC81 A0
.47 8F24
1.00 10P13
'88 30FL13 .64
.90 WATCHED TRANSISTOR SETS:17408
U404
1'10 CC189 60 Q875/20
76 LP16 (A0119. A0154. A0157, AA120) 4$p
OAKS
.70 8F25
1.17 10P14 8.84 SOFL14 -82 ALeO 117 ECC82 .89 5M87
PCF80 47
1.00 17801
10 y.r pack. 1-0061D A 2-0081, 55p.
eAMBA 70 6F28
-76 301.15
40 ECC83 10 5308803
.78 12A6
19 ATP4
U4020
2.50 CF82 50 Q895/10
15 1-0044 2-0045, 1510. 1-0002D. a
5CC84 .40
6AN8
70 12AC6 10 30L17 .78 A
18 61,32
PCF84
5Y51
60
70
VP29
100
'Si 2-0002 ßp. S.t of 8-0088 849.
6AQ6
A231
10 &CC85 47
AS 808G
.60 124136 -SO 30P4MR
OARS
80 E0088 100
.80 6058.4 -88 12AE6 90
185 ÁZ43
6A137
1.17 6656
98 12AT6 .47 90P12 40 5183 214 E0088 45 VALVES ALSO REQUIRED TO P171102185. LOOSE OR BOXED, BUT MUST BE NEW. OFFERS
8AT8
.53 60177
-88 12AU6 48 30P19/
CL33 1.86 EOC189 .80 MADE BY RETURN.
8AU6
40 6H8GT 10 12AV6 69 30P4 18 CY1C 110 ECC807 141 All goods are unused, tested, and guaranteed. Despatch charges:-25p on all orden below E30 in
6AV6
.70 50780 60
6$ BJSGT .58 12BA8 .68 30PL1 110 CY31
over l0 post tree. Orders despatched same dap as received. Any parcel Insured against
6AW8A -90 6J8
16 11213E6 69 S051.13110 DAF91 40 50782 60 value. Ordere
6AX4
-88 6J70
.36 72BH7 19 30PL14 119 DAF98 10 ECF88 .89 damage In transit for 5p per parcel extra. Terms of business available on request. Many others la
-00 5CF8042d8 stock too numerous to list. Please enclose S.A.E. for reply to any correspondence.
61180
.36 fiJUBA 58 12BY7 86 30PL16 10 0090
1'
51
.0
.
.
'
ü
N
2,1parcel
8
Practical Wireless, May 1976
15
-120 Watts!
The HY5 is a mono hybrid amplifier ideally suited for ail applications. All common input functions (mag. cartridge, tuner,
etc.) are catered for internally, the desired function is achieved either by a multi -way switch or direct connection to the
appropriate pins. The internal volume and tone circuits merely require connecting to external potentiometers (not included).
The HY5 Is compatible with all I.L.P. power amplifiers and power supplies. To ease construction and mounting a P.C.
connector is supplied with each pre-amplifier.
APPLICATIONS
FEATURES
HY
5
P ream pf
ifier
Complete pre -amplifier In single pack
Multi function equalisation
HI -Fi
Miners
Disco
Guitar and Organ
Public address
Low noise
Low distortion
High overload
Two simply combined for stereo
SPECIFICATIONS
INPUTS. Magnetic Pick -up 3mV; Ceramic Pick -up 30mV; Tuner 100mV;
Microphone 10mV; Auxiliary 3- 100mV; Input Impedance 47k( at 1kHz.
OUTPUTS. Tape 100mV; Main output 500mV. R.M.S.
AC1 IVE TONE CONTROLS. Treble ±12dB at 10kHz; Bass ± at 100Hz.
DISTORTION. 0.1 %, at !kHz. Signal /Noise Ratio 68dB.
OVERLOAD. 38dB on Magnetic Pick -up.
SUPPLY VOLTAGE ± 16 -50V.
Price £4-75 + £1-19 VAT, P &
P
free.
The HY30 is an exciting New kit from I.L.P. it features a virtually Indestructible I.C. with short circuit and thermal protection.
The kit consists of: I.C., hestslnk, P.C. board, 4 resistors, 6 capacitors, mounting kit, together with easy to follow construction and operating instructions. This amplifier is ideally suited to the beginner In audio who wishes to use the most up-todate technology available.
APPLICATIONS
FEATURES
HY3O
5
Watts into
Updating Audio Equipment
Guitar Practice Amplifier
Test Amplifier
Audio Oscillator
Complete Kit
Low Distortion
Low Distortion
Short, Open and Thermal Protection
Easy to Build
SPECIFICATIONS
8c
OUTPUT POWER. 15W R.M.S. into
DISTORTION. 0.1% at 15W.
INPUT SENSITIVITY. 500mV.
80
Available
June 76
FREQUENCY RESPONSE. 10Hz- 18kHz -3d8
SUPPLY VOLTAGE. ±18V.
Price £475 + £1.19 VAT, P & P free.
The HY50 leads I.L.P's total Integration approach to power amplifier design. The amplifier features an Integral heatsink
together with the simplicity of no external components. During the past three years the amplifier has been refined to the
extent that it must be one of the most reliable and robust High Fidelity modules in the World.
HY
25
FEATURES
Low Distortion
50
Watts into
APPLICATIONS
Medium Power HI -FI systems
Low power disco
Guitar amplifier
Integral,Heatalnk
Only flue connections
7 Amp output transistors
No external components
SPECIFICATIONS
8s2
INPUT SENSITIVITY. 500mV.
OUTPUT POWER 25W RMS into 80
LOAD IMPEDANCE. 4 -160
DISTORTION. 0.04% at 25W at 1kHz
SIGNAL /NOISE RATIO. 75dB.
FREQUENCY RESPONSE. 10Hz-45kHz
SUPPLY VOLTAGE. ±25V.
SIZE 105 x 50 x 25mm
-30B.
Price £820 + £1.55 VAT, P á P free.
The HYI20 Is the baby of I.L.P.s new high power range, designed to meet the most exacting requirements Including load
line and thermal protection this amplifier sets a new standard in modular design.
HY 120
60
Watts into
APPLICATIONS
FEATURES
Very low distortion
HI -Fl
High quality disco
Public address
Integral heatslnk
Load line protection
Thermal protection
Monitor amplifier
Guitar and organ
Five connections
No external components
8c
SPECIFICATIONS
INPUT SENSITIVITY. 500mV.
OUTPUT POWER. am RMS Into 80.
LOAD IMPEDANCE. 4 -160
DISTORTION. 0.04°% at 60W at 1kHz.
SIGNAL /NOISE RATIO. 90dB.
FREQUENCY RESPONSE. 10Hz -45kHz
± 35V
SUPPLY VOLTAGE.
- 3dB.
SIZE 114 x 50 x 85mm.
Price £14.40 + £1.16 VAT, P & P free.
The HY200 now improved to give an output of 120 Watts has been designed to stand the most rugged conditions such as
disco or group while still retaining true HI -FI performance.
HY 200
120
Watts into
Thermal shutdown
Very low distortion
Load line protection
Integral hestslnk
No external components
8Q
SPECIFICATIONS
INPUT SENSITIVITY, 500mV.
LOAD IMPEDANCE, 4 -180.
SIGNAL /NOISE RATIO, 96dB.
SUPPLY VOLTAGE, ± 45V.
POWER SUPPLIES
Price £21.20
+
£1.70
APPLICATIONS
FEATURES
HI -FI
Disco
Monitor
Power slave
Industrial
Public Address
OUTPUT POWER, 120W RMS into 80.
DISTORTION, 0.05% at 100W at 1kHz.
FREQUENCY RESPONSE, 10Hz- 45kHz -3dB
SIZE 114 x 100 x 85mm.
free
PSU70 suitable for two HY120's£12 SÓl plus1£1.00 VAT / P/P free
PSU90 suitable for one HY200 E71.58 plus £0.92 VAT P/P free
VAT, P & P free.
TWO YEARS GUARANTEE ON
I.L.P. Electronics LTD.,
Please supply
I
Enclose, Cheque O
Name
a,
Postal Orders O
ALL OF OUR PRODUCTS.
..eRi0(:SLIg21113.HOUSE, NACKINGTON, CANTERBURY, KENT
Money Order O.
CG.OFFAICD
ENO.: 1032630
Total Purchase price
Please debit my Access account O Barclaycard account O
Account number
Address
Signature
Practical Wireless, May 1976
9
EUI4ItJfltJEfflJ!s
--(TRANSISTORS
BRAND NEW FULLY GUARANTEED
Type
Price
AC117K 1.31
AC126 0-11
AC126 0-14
AC127 P11
AC128 111
AC128K Odi
11.18
AC141
AC141K N'M
AC142 4.19
AC142K 4-26
AC153K'124
011
4.26
N21
AC176
AC176K
AC180
AC180K
140
4.20
1d0
AC181
AC181K
AC187
AC187K
AC188
AC788K
AD140
AD142
AD143
AD149
AD150
1117
1123
'0.10
'0ß3
'1.49
'0.55
'0-49
145
'1.65
1130
AD161
AD162
A01616
'1131
AD162(MP)
rQ
11-22
AF114
AF115
AF116
AF117
AF118
AF124
AF125
AF126
AF127
AF139
'P22
0-22
'I1.22
'1.32
0-21
028
0-21
0-21
11.31
Type
Price
Type
AF178
AF179
AF180
AF181
AF186
AF239
AL102
AL103
BC107
BC108
BC109
BC113
BC114
BC115
BC116
BC117
BC118
BC119
BC120
BC137
BC139
BC140
0-51
14.51
BC169
BC169C
BC170
BC171
BC172
BC173
BC174
BC175
BC177
BC178
BC179
BC780
BC141
BC142
BC143
BC115
BC147
BC148
BC149
BC150
BC151
8C152
BC153
BC154
SCI 57
BC158
BC159
BC160
BCI61
BC167
BC168
'6.51
4-51
'0.51
0.30
"0.75
0.75
'
'0./1
6.00
0-Q
0-10
F1S
BC181
0.16
1.16
6.29
11.20
BC301
0-11
0.11
0.11
BC302
BC303
BC304
BC327
8C328
BC337
BC338
0 tl
0-Q
0.51
0.16
0.41
''0-31
"0.31
1.31
'0.31
0.46
0.011
0.0/
1'Q
0.10
O
-20
O .111
.6.44
'0.51
0.10
010
Type
e-10
0.10
0-09
0.09
BC440
BC460
BD115
BD116
BD121
BD123
1.111
0-09
0-15
130124
BD131
6.22
0.16
BD132
' 0.16
BD135
0-16
80133
'0.25
O
BC182
BC182L
BC183
BC183L
BC184
BC784L
BC188
BC187
BC207
BC208
BC209
BC212
BC212L
BC213
BC213L
BC214
BC214L
BC225
BC226
BC251
"0.31
Price
BD137
BD138
BD139
BD140
BD155
BD175
80176
4-29
130177
'0.29
80178
F11
BD179
0-11
80180
1.12
0-11
0.16
BD185
BD186
80187
80188
80189
0-10
0-10
0.10
0-11
0.21
BF117
BF118
BF119
BF152
BF153
BF154
1.53
0.01
Nd1
0.67
'0.70
'0.30
'0.40
BD195
BD196
BD197
BD198
BD799
BD200
0-10
'0-26
'9.25
1-21
80205
0-37
0-12
BD206
BD207
BD208
BDY20
BF115
-12
0-12
12
Price
e.46
'0.71
0.71
e-56
0.4e
0.41
0.71
'0-49
61F155
8F156
0.56
BF157
BF158
BF158
BF173
BF176
BF179
BF180
0-61
BF181
0-67
0-41
0-41
0-46
0.51
'0-81
10. 51
O -56
0.61
0 15
0.36
'0-71
'0-71
0-31
0.61
4.67
'0.67
90.71
0-71
'0.07
'0-67
0-T1
071
'0.77
0-77
0-07
0-17
'0-92
O
0-12
e12
'0.21
'0.36
"0.46
0.56
0.56
0.36
' 0.31
10.11
0.3$
036
'0.25
8F274
BFX29
BFX84
BFX85
BFX86
BFX87
BFX88
BFY50
0.92
4.90
'0.05
10.01
0-S1
1.90
'0.00
'1.02
'0.15
0-19
"0.25
0.22
'0 22
'0.22
'0.13
'013
6.13
BFY51
BFY52
Glass Sub -min. General purpose Germ. diodes
Germanium transistors like 0081, AC128
60200mA Sub-min. silicon diodes
20 PNP Sit, planar trans. TO -S like 2N1132, 2N2804
U11
1.115
20 NPN SII. planar trans. TO -5 like 2N696,214697
20 Silicon NPN transistors like BC108
U19
30 Fast switching silicon diodes Ilke 161914 Micro -Min.
U26
101 Amp SCR's TO -5 can. up to 600 CRS /25 -600
U29
25 Zener diodes 400mW DO -7 case 3 -18 volts mixed
U32
20 Silicon planar NPN transistors TO -5 BFY50/51/52
U3$
7 3A SCR. TO66 up to 600 PIV
U45
U46
20 Unllunction transistors similar to TIS43
9 NPN Sii. Power transistors like 2N3055
U48
Code No's mentioned above are given as a guide to the type of
In the Pak. The devices themselves are normally unmarked.
U
1
U 4
120
30
U 5
Price
0.60
DIODES
Type
Price
010
.11 21
442
I.15
BA100
BA116
BA126
BA143
BA154
BA156
BA173
88104
BY100
131126
BIM 27
4.12
0
0
BY128
51164
14
15
Price
Type
Price
'0.15
'0 16
0A70
0A79
'0.07
0-15
0.18
4.60
0.60
'0.60
0.60
0.60
4-10
BYX38300
43
0A200
0A202
'0 07
'0.09
0A85
0A90
161914
1N916
1N4148
0 07
LSO
.£120
2
0.00
£1 ß0
0.60
£1 ß1
10
0.60
6
Amp
Amp
Amp
0-6A
50
100
150
200
400
600
800
0-19
'0.29
'0-29
'0.13
BSY95A '0-13
BUi05 1d0
-- --
0
51
'6
65
'0
S1
50
100
200
400
600
800
1000
1200
10
300mA
(DO 7)
0-Os
COS
o
M
0-07
0-0O
011
013
-
'0
'0-26
'Oß6
Oß4
OC170
OC171
0C200
OC201
0.55
Oß9
0ß6
OC202
OC203
OC204
MJE2955'0.11
MJ E3055'0 57
-
.
OCP71
NSL4931
0-41
ORP61
10-41
'0-47
N-49
TIP29
TIP30
TIP31A
TIP32A
10.40
10.45
OC26
.11.3/
*ono
0-57
'0.19
TIP41A
TIP42A
0.w
'0-51
0070
'0.13
'0.10
0072
0074
'0-15
'0.15
0071
10.10
2N696
2N697
2N698
2N699
Case
TO5
TO66
TO48
0 52
0 60
Price
'0.97
0.07
0
07
0
06
'0.07
'0 OS
'0 06
100
4.36 '0.40 10-51 '0.54 1-15
0.41 '0-51 0.57 0.59 1.43
400V
200V
'0.31
'0.51
0.51
'0
71
'0.61
77
'0
92
1
77
12
'0
100+
'Np
for '8140.
500
for LS,
When ordering please state NPN or PNP
JUMBO SEMICONDUCTOR PAK
Transistors -Germ. and Silicon.
Rectifiers- Diodes. Triacs -Thyristors- I.C.'s
Zeners. ALL NEW AND CODED.
Approx. 100 pieces only 1.85p
0.50 0-57 0.62 4-62 '1-63
0.57 0-62 '0.71 '0.77 1.79
'0-69 0-71 049 0.90
0
81
'0
92
'1 22 '1 39
-4
ZENER DIODES
07
FULL RANGE IN STOCK.
400mW Sp
5W 17p
750mA
(SO 16)
0.01
5-07
0-Q
9.14
0-15
11.11
0.21
1.32
TIFI R
00.15
00.15
0-10
010
'6.21
'9.21
'0ß4
'6.24
'011
'016
'0.73
0.50
4-11
'O-18
2N2907
0.15
2N2005A 0.19
2N2906 10.12
2N2906A '0.14
2N2907A 0.10
2N2923
0-IS
2N2924
0.15
2N2925
0.15
2N2926G 0.00
2N2926Y 0-09
2N29260 O -Q
2N2926R 0.07
2N2926B 0.07
2N3053 '0.15
2N3054
40
2N3055 '1.40
2N3402 *0-21
2N3403 0.21
1
2N3404
2N3405
2N3614
'0-29
'0.43
'0-00
2N3615
0.76
2N3616
2N3646
2N3702
0.09
0.09
'0.76
2N3703
2N3704
2N3705
2N3706
2N3707
2N3708
2N3709
2N3710
2N3711
2N3819
2N3820
2N3823
2N3903
2N3904
2M3905
2N3906
2N4287
2N4288
2N4289
2N4290
2N4291
2N4292
2144293
2145172
2645457
2 /45458
2N5459
40361
40362
Price
1.09
0.01
COI
0.01
0.01
0.61
0-04
0.09
0.09
8.14
'0.40
0.11
0-12
0.12
0-14
0.14
0-10
0.18
Ole
0.1S
0.18
0-11
11.15
9.12
120
'0.28
.0-28
'8.30
'0.35
{
HANDBOOKS
TRANSISTOR DATA BOOK
DIE
1 227
Pages packed with information
on European Transistors. Full specifica-
tion Including outlines.
Price íE2.05 each
Pages of cross references and
equivalents for European, American and
Japanese Transistors. This Is the most
comprehensive equivalents book on the
market today and has an Introduction In 13
Pricet£24S each
languages.
EWE 75 256
'Np
£I.
4-11
4-10
' /.is
2N2905
Type
TRANSISTOR EQUIVALENT BOOK
25 -99
for SOp. 50 for
for £14.
2N2904A
'0-15
'0.11
0-14
V.A.T. to prices marked
GP Switching Trans
1,000
'0-11
Price
'6.34
.
11
10 20
'0 36
TO18 SIM. TO 2N706;8
All usable devices. No open and shorts. ALSO
AVAILABLE IN PNP similar to 2N2906, BCY70.
20
2N2646
2N2904
Please add 8% to prices marked
Remainder add 75%.. Do not add
'0-10
WATT SILICON TO3 METAL CASE
Vcbo 100V. Vceo 60V, IC 15A, Hfe, 20 -100 suitable
replacement for 2N3055, BOTI1 or BDY20
-24
Type
0-Q
VAT CHAT
100V
0
'0-M
2N2219 '010
2N2219A '0-10
2N2220 '0.22
2N2221
00.19
2N2222
2N2368 4-10
2N2369 '0.12
2N2369A 9.12
'I11 6572
'0
Price
2N2218A'0-19
TIS43 '0 25
UT46
'0-20
ZTX107 0 07
ZTX108 0 07
ZTX109 0 07
ZTX300 0 07
ZTX500 0 09
60
'0-45
0.25
0-16
2N2218
46
ORP60
'0-20
2E12148
ORP12/
'0-36
0C42
0C44
0C45
2N1711
2N2147
'1.M
0C19
OC20
OC22
0C23
0C24
0C25
0C41
2N1613
"1 20
'1139
0C205
MJ E3440 O S1
MPF102 4-20
MPF104 '0-20
MPF105 '028
1
R
Ply
0
0C139
0C140
0C169
THYRISTORS
6.13 '0.15
0.1S 0-13
0-10 0.22
0.22 '0-21 0ß0 0-25 4-36
0.25 0-30 91.25 0.25 0.41
'1-31 0-35
0.31 '0.44 '0.25 '0.30 'CH
0.30 0.39 O.SS
0-39 0.48 '0-89
10
20
30
2 /41309
10-19
20
23
0082
GP300
device
10A 16A 30A
7A
3A
5A
5A
0 8A IA
TO18 TO92 TO5 TO66 TON TO64 TO48 TO48 TO48 TO48
PIV
41 21
10.16
'50P
0A91
OA05
'107
OA81
'0-51
"0 26
2N708
2N914
2M918
2N1131
2N1132
2/41302
2 /41303
2N1304
2N1305
2N1306
2N1307
2N1308
'016
0081
OC81D N16
'0-16
00820 '0-16
'Oß0
0083
'0
2N706A
0.26
OC77
'0-16
'0-16
0C28
0C29
0C35
0C36
2N706
'0-1S
TRIACS
1
Type
4.14
0.07
OAIO
OA47
0.16
4-11
4-16
Type
Price
016
0075
0076
'0.16
300mW 400 PIV (min) SUB -MIN FULLY TESTED
Ideal for Organ builders
30 for 50p. 100 for E1 50. 500 for £5. 1.000 for Ef-
115
Type
4.13
SII. G.P. DIODES
UNTESTED PAKS
Description
Pak No.
-12
Type
Price
Type
BFY53
BSY18
BSX20
BSY25
BSY26
BSY27
BSY28
BSY29
BSY38
BSY39
BSY40
BSY41
BSY95
MJE521
0.10
0-10
0-92
BF194
BF195
BF196
BF197
BF198
BF199
BF257
BF258
BF259
BF262
BF263
BF270
BF271
BF272
BF273
4.61
130190
0.36
0
Type
0.31
'0.37
130136
-25
1-01
0.00
0.99
0-09
0.09
0-09
O
Price
Volts
10W '30p
2-33
and
DIODE EQUIVALENT BOOK
DE 74 144 Pages of cross references and
equivalents for European, American and
Japanese diodes, Zeners, Thyristors,
Triers, Discs and L.E.D.'s.
Price t£lA I each
THE WORLD'S BROADCASTING
STATIONS
WBS 75 An up to the minute guide for
those Interested In DX -ing. Contains all
the world's broadcasters on SW, MW and
LW, as well as European FM /TV stations.
TTL DATA BOOK
Price-MI-SS each
DIC 75 Now complete Data book of 74
series TTL (741X-74132).- Covering 13 main
manufacturers In the U.S.A. and Europe,
this book gives full data as well as equivaPricef£3-74 each
lents.
A full range of technical books available
on request.
AA
Postage and Packing add 25p
shown.
otherwise
unless
Add extra for airmail. £1
minimum order.
Amp 1-5 Amp 3 Amp 10 Amp 30 Amp
Plastic (SO 10)
(SO 10) (SO 10) (TO 48)
1
0.05
0.06
N4003 0.07
N4001
N4002
N4004
N4005
N4006
N4007
0-011
0.01
0-10
0-11
0.07
0.09
0.12
0.14
I IS
0-10
0-23
0.20
0.14
0.16
0.21)
Ode
0-33
0.35
0-44
0.54
0.19'
0ß1
0ß31
0.35
0.42
0-S1
0.14
0.60'
0.56
0-69'
0.93'
1.
S
1.76'
I AM'
2-31'
2.10'
P.O. BOX 6, WARE, HERTS
Practical Wireless, May 1976
MUCT RS
EflflhI=C
Untested LIN Paks
Limer /Cs
Type
Quant/fies
72702
72709
72709P
72710
0.49
0-23
0.10
0.32
0-28
0.26
25
1
72741
72741C
72741P
72747
72748P
SL201C
0ß8
0-79
0.35
0.46
0 44
0-21
0-19
0-31
0.27
0.25
0.27
0-74
033
0.42
7401
7402
7403
7404
7405
7406
7407
7408
7409
7410
7411
7412
7413
7410
7417
7420
7422
7423
7425
7426
7427
7428
7430
7432
7433
7437
7438
7440
7441
7442
7443
7444
7445
7414
7447
25 100+
0-42 0.37
9-42 0-37
0.65 0.55
0.811 0-03
TAA350E1.71E1-57E1-57
ixA703C 0ß9
itA709C 0i9
µA711C 0-32
026
0-61
0-31
0-22
0.17
0-31 0.20
032 031 048
140712C
µA723C 045
0-37
0-24
0.18
Quantities
1
76003
76023
76660
LM380
NE555
NE536
25
100+
L130 E134 E130
E139E134E130
035 0-0 0J3
063 0'90 038
0.45 0.43
058 0-06
0.40
0.53
- -
T8A800E1.39E134£1-30
ZN414 E1.11
0,78
7453
0.60
0-12
0.12
0-12
0.11
0.11
0.11
100+
0.76
0.10
0-10
0-10
7454
0.12
0-11
0-10
7460
7470
7472
7473
7474
7475
7476
7480
0.12
0.25
0.22
0.26
0.27
0-18
0.25
0.50
0.11
0.10
0-23
0-20
0.22
0.23
0-44
0-23
Type
0.11
0,11
100+
0-09 0.05
0-09 0-0
0.10 0.09
0-10 0.09
0-13
0.12
0-11
0.11
25
1
0.09
0-10
013 0.12
0-25
0,25
0,15
0-15
0.09
0.23
0ß5
0ß6
0.28
0ß8
0.24
0-24
0-14
0.14
0-09
0,22
0-25
0-26
0.27
0-27
0.11
0.27
0.12
0.28
0-30 0ß5
0-30 Oßs
0.30 0ß8
030 0-25
0-42 035
0.12 011
0.30 0.25
0-39 0-37
0.30 0ß9
030
0-12
0-64
0-05
7448
7450
7451
0,23
0-23
0-13
0-13
0-00
0-21
0-24
0.25
0ß6
Oß6
0-25
0.36
E105 E1 .N
£1.10E1-05E130
0.95
0.67
0.80
0-37
0.0
0-43
0-43
0.13
0.70
0-85
0.46
0-24
0-48
0.81
0-96
0-0
044
0.95
0-79
0-94
0.56
035 033
0.50
0.42
0-42
0-42
0.0
0.0 0.0
9-40
0.40
035
0.56
0.53
090
0,58
0,41
0-41
0.41
0.64
0.54
030 0.36
0-30
0-34
0-54
0.81
0.00
0.36
032
0.52
0.79
035
ß5 E1 20 E11 S
0ß4 0ß6 0.25
74118
74119
-
0ß5
E130 0.98 0.96
74111
0 E130
035 0-63
0.24
E1ß5E120E1.15
0-32 0.30 029
7492
7453
7494
7495
7196
74100
74104
74105
74107
74110
E1 10
0.21
E2.90E2.80E2-70
7491
010
0.25
0.35
0-25
0ß9 0.26
0-11 0.10
0.52 0-90
0.53 0.01
E1 -10 E1
0-53
0-98
0-00
7482
7483
7484
7485
7488
7489
7490
0-26
0.10
0.21
0.26
0.24
£1.02E1-00
7481
0ß6
25
1
E1
74121
Type
74150
74151
74122
74123
74141
74145
74153
74154
74155
71156
74157
74160
74161
74182
74163
74164
74165
74166
74174
74175
74176
74177
74180
74181
74182
74184
74190
74191
74102
74193
74191
74195
74198
74197
74198
74190
1
0.50
0.56
040
0.95
É130
0.76
0.95
Quantities
Type
25
1
BP930
BP932
BP933
BP935
BP938
*
T5014
0.14
0.15
0-13
0.14
0.15
0.14
015 014
0.15 014
100+
0-13
0.13
0.13
0.13
0.13
BPO44
0ß8 0ß6 0 23
014 013 012
BP945
131.946
BP910
0.25
0.65
BP951
1
14
Type
1
0.29
0.23
030 0.54
031
25
100+
028 025
0.35 0.32 0.30
0.14 0.12 0 10
0.15 0.13 0.11
0
14
0.12
VAT
PLEASE ADD 8%
TO ITEMS
MARKED
REMAINDER
ADD 25%
1
*
J
OUR SPECIAL PRICE
L1ß0
P&P
0.94 0.92
ILI 2S E1 ß0
0.72
0-70
0-75
0.93
0.90
E130 0.98
E100 0.9s
£1.00 0.98
0.76
0.60
0.80
0-95
E1.00
0.91
075
0-91
0.00
0-06
0.96
0.911
E1ß5 E120E7.15
C1ß5 E1ß0E1.15
£1-45E1-44E139
0.95
0.93
0-0
031
E1-18Et.11E135
E1.16E111£1-00
E7.16 E1.11 L1.00
E200 E1-50 E10
0-90 0-0 0.86
E1.47 E1.02 E1.50
E1.50E1J5£1.40
f1.0E1.45E1-40
£1.15E1i0E1.05
£1.15 £1.10 LI -05
E1.15f110£1-05
0-00 0-75
E130 0.95
0.90
0-74
0.0
0-0
E210 L200 E130
E1.95 E1.90E195
Postage and Packing add 25p
unless otherwise shown. Add
extra for airmail. Minimum
order V.
* /adicalors
3015F
Minitron
7
Segment Indicator
TO.3 Plastic Encapsulation
µA.7805/L129 5V
(equiv. to MVR5V) E1ß5
µA.7812/L130 12V
(equiv. to MVR12V) L1.25
µA.7815/L131 15V
(equiv. to MVR15V) £1-25
uA.7818 18V
(equiv. to MVR18V) E1 -2S
E1.11
-
* Untested TTL Paks
Pak. No. Contents Price
0 60
UIC00 =12 x 7400
Quantifies
1
25 100+
0-14 0-13 0-12
0.42 0.40 9.35
0.42 0.40 0.30
0.42 0.40 0.30
0.42 0.40 0.38
Regulators
069 064 0.52
0 16
BP962
BP0083
BP9094
BP9007
BP9099
to Identify.
100+
0.15 0-46
0.56 0-54
0-58 0-56
* Voltage
OIL Sockets
pin type
TSO1616 pin type
TSO24 24 pin type
BPS8 8 pin type (low cost)
BPS14 14 pin type (low coat)
BPS16 16 pin type (low coat)
f
Quantifies
25 100+
0-15 0.14 0-13
Type
0.90
9.99
0.99
25
0.74
0.93
£1-00
0y
-
E1.50E1J5E1-10
E1-00
0.95
0.0
Many coded devices but some unmarked -you
DTL 930 Series
,
--
10 x 709
ULIC709
7 x 710
ULIC710
ULIC741 = 7 x 741
5 x 747
ULIC747
7 x 748
ULIC748
APPROX. 200 PIECES
Assorted fall -out integrated circuits, including:
Logic, 74 series, Linear, Audio and D.T.L.
Devices may be mixed to qualify for quantity price. (I TL 74 series only). Data is available
for the above series of I.C.'s In booklet form. PRICE 35p.
*
Manufacturers "Fell Outs" which include
Functional and part Functional Units. These are
cfassiffed as 'Out -of -spec' from the makers'
nerf rigid specifications, butera Ideal for learning about I.C.'s and experimental work.
Price
Contents
Pak No.
Mum oM IC Pa*
0.43 0-40
STILL LOWEST IN PRICE. FULL SPECIFICATION GUARANTEED. ALL
FAMOUS MANUFACTURES
Type
7400
1
0.40
SL702C 0.19
TAA263 0.74
TAA293 0.93
SL701 C
7fSeriesTtL /C
*
BI -PAK
Type
Quantifies
Type
100+
0.42
0-19
0-17
0.26
0.26
0.24
''
UIC01=12x7401
UICO2=12x7402
UIC03=12x7403
UICO4=12x7404
UIC05=12x7405
UIC06= 8x7406
UIC07= 8x7407
UIC10=12x7410
UIC13= 8x7413
UIC20=12x7420
UIC30=12x7430
UIC10=12x7440
UIC41= 5x7441
UIC42= 5x7442
UIC43= 5x7443
UIC44= 5x7144
UIC45- 5x7415
UIC46= 5x7446
UIC47= 5x7147
UIC48= 5x7448
UIC50=12x7450
UIC51=12x7451
UIC53-12 x 7453
UIC54=12x7454
UIC60-12 x 7460
0.0
030
0.0
0-0
0-0
0-50
0-0
030
0-60
0-0
0.90
030
0-0
030
0.0
0
0
0.00
0.0
010
030
030
0.60
0-0
0.60
0.0
Pak No. Contents Price
UIC70=
UIC72=
UIC73=
UIC74=
UIC7S=
UIC76=
UIC80=
8x7170
8x7472
8x7173
8x7174
8x7475
8x7476
5x7480
UIC81m 5x7481
UIC82=
UIC83=
UIC86=
UIC00=
UIC91=
UIC92=
O-N
030
0
00
0 0
0
0
0
0
0
0 90
5x7432
O30
0
5x7483
5x7438
530
5x7400
0 60
0 00
5x7401
5x7402
0
U1C93= 5x7493
UIC04= 6x7494 0-0
0.0
UIC85= 5x7195
UIC96= 5x7408 0.0
UIC100= 5x71100 0
UIC121= 5x74121
UIC141= 5x74141 040
0
,
00
0
0
00
UIC151- 5x74151
UIC151- 5x74154
0i0
0.0
U1C193- 5x74193 0 M
UIC109= 5x71109 P0
UIC XI 25 Assorted
74's
E1 50
IMPAIK
P.O. BOX 6, WARE HERTS
Practical Wireless, May 1976
Marshall
Marshall (London¡ Ltd Dept: PVil
Cricklewood Broadway London .NW23FT Tel. C1-452 016112
Telex: 21 -792
S 85 West Regent St Glasgow G2 200 Tel 041.-3324133
&
Straits Parade Fishponds Bristol BS16 2LX
A
42
.
-1
8.6629 -0
Tel
0272 65420172
& 27
Rue Danton Issy Les Moulineaux Paris 92 Tel 644 2356
Trade and export enqulnes o. el: ale
Catalogue price 25p
Our range covers over
7,000 items. The largest selection in
Top 200 IC's TTL, CMOS & Linears
Ei
1
01
1,,d
57.2958'
h10
2 -30259
r71e2e
Scientif ic
CA3020A LI 80 CD4049
CA3028A 79p CD4050
CA3035 LI 37 C04510
CA3046
70p CD451 I
CA3048 L3 II CD4516
CA3052 L1 61 CD4518
CA3089E 11.96 CD4520
CA3090Q L4d3 LM301A
CA3130
88p LM308
CD4000
18pLM309K
C04001
18p LM380
CD4002
18pLM38I
';
3-14159
^
LASKYS now offer this
Sinclair Scientific
Calculator for a
fraction of the
original cost. All parts are
supplied all you need
provide is a soldering iron
and a pair of cutters,
CD40I7
CD4018
t'
-9.9999 x 10 -9 to
9.9999 x 1099. Post -fixed operators. Po t -fixed operators (reverse Polish
notation): allow chain calculations of unlimited length. 'Upper and lower case'
operation. Basic arithmetic keys each have two extra functions. Pocket -sized.
2'x $ °. Weight: 4oz .Trim -f it plastic carrying case.
4
ROMFORD 86 South Street. 20218
SOUTHEND 255i206Churchill West. 612241
SLOUGH 65 Q ueeilsmere Centre. 7524401
SWINDON 12 Brunel Plaza.
TUNBRIDGE WELLS 53/57 Camden Rd. 23242
WOLVERHAMPTON 30Wullrum Way. 23384
2N2IO2
60p
2N2147
2N2148
7Bp
94p
2N2218A 47p
2N2219A 52p
2N2220 1Sp
2N2221
I8p
2N2222 20p
2N2369 lOp
2N2646 55p
2N2904 40p
2N2905 47p
OINBqB
a)
CLUB
2N2907
2N2924
2N2926G
2N3053
2N3054
2N3055
To LASKYS CUSTOMER SERVICES DIVISION (Dept. J 2)
Audiotronic House, The Hyde, London NW9 6JJ. Tel :01-200 1321
Sinclair Scientific Calculator Kits at £6.50
i
I
II
(inc. p/p & Ins.)
Please send me FREE Hi -Fi catalogue price list
money order
postal order
enclose cheque
- - ---
England No. 347947 at Lower Grosvenor Place, London SW1
BBBBI
12
11p
20p
12p
25p
60p
.
6Sp
28p
2N3714[1-38
2N3716 LI-B0
I
wish to pay by Barclaycard /Access /Diners Club and my number is
ilmtpstered in
2N3391
33p
2N3392 ISp
2N3393 ISp
2N3440 59p
2N3442L1-40
2N3638 I5p
2N3702 12p
2N3703 13p
2N3704 ISp
2N3706 115p
2N3708 14p
INAME
ADDRESS.
I
32p
16p SN74145 72p TBA810
75SN744IAN68pSN74150L1 20 TBA820
98p
70pMC1469R
2N2906
SIGNATURE
TOTAL PURCHASE PRICE
LI -20
CD4041
lip
CROYDON 1046Whitddt Centre. 6813027
COLCHESTER Unil AS Lion Walk
Shopping Centre, opening FEBRUARY
DARTFORD The Arndale Centre. 32 73481
KINGSTON 38,40 Eden Street 5461271
LEICESTER 45 Market Place. 537678
LEWISHAM 29 Riverdale. The Centre. 3182297
NORTHAMPTON 78 Abington St. 35753
NOTTINGHAM 5 -7 lower Parliament St. 48987
OXFORD 16 Westgate Centre. 722870
READING 6 Friars Walk, Friar St. 595459
RICHMOND 32 Hill Street. 9481441
75pSN76033NL1.91
30p TAA550
CD4031
2N696
22p
2N697
16p
2N698
82p
2N699
S9p
2N706
14p
2N708
17p
2N916
38p
2N918
2N1302 184p
2N1304 26p
2N1306 31p
2N1308 47p
2N17I1 27p
}'x
IPlease send me
plus 50p p &p
28p SN7495
28p SN7496
16pSN74100LI
23p SN74107
23pSN74118
68p TAA263
6Bp TAA300
90p SN7432
52p MC1351P 80p SN7437
98p MCI4553 [4.07 SN7438
88pMCI466LU
26pSN7494
50 SN7440
[I
114
10TAA350ALI 96
85pTAA611C
18
23pSN74119LI 75TAA62I L203
15p SN7412I
32p TAA661 B LI 03
12pSN74122 42pTBA64IBL1 25
28p55474123 6Sp TBA651 LI 69
28p SN74141 75p TBA800
89p
BRISTOL
Boo
It's
POPULAR SEMICONDUCTORS
-digit mantissa and 2 -digit
exponent, both signable.200decade range.
BRISTOL 16 -1820 Penn Street. 20421
CHATHAM The Pentagon Centre. 407104
4Ip5547413
6Ip 5N7416
LI .88 SN7417
LI 99SN7420
LI .99 SN7423
London, Glasgow, Paris and now
our service that makes us grow
5
3 Lisle Street, WC2. 01- 4378204
118 Edgware Road, W2. 01.723 9789
193 Edgware Road, W2. 01.723 6211
Oil Edgware Road, W2. 01.262 0387
346 Edgware Road, W2. 01- 7234453
382 Edgware Road, W2. 01.7234194
109 Fleet Street, EC4. 01.353 5812
152 Fleet Street, EU. 01-353 2833
BIRMINGHAM 116 Corporation SL 2363503
BRENT CROSS Unit 019 Brent Cron
Shopping Centre. Now-open
16pSN7416I
Blip
87 SL610C [2 35 SN7451
16p SN74162
BBp
LI .87 SL61 IC E235 SN7453
16p SN74163
B8p
48p SL6I2C L2 35 SN7454
16p 5N74164 L1.60
LI 17 SK620C L3 50 SN7460
16p SN74165 [I -60
[I 88SL621C
50SN7470
29pSN74167 E3.30
98p SL623C E5 24 SN7472
2Ip SN74174
99p
L2 07SL640C L4 005N7473
3IpSN74175
70p
75p SN7400
16p SN7474
31p 5N74176 LI .14
38pSN7401
16p SN7475
45p SN74180 LI 10
38p SN740IAN29p SN7476
30p SN7418I LI 95
45p SN7402
16p SN7480
42p SN74190 [I .116
38p SN7403
16p SN748I LI 00 SN74191 El .86
17p SN7404
19p SN74R2
6Sp SN74192 LI IS
19p SN7483
66p SN7405
82p 5N74193 LI IS
40p SN7406
36p SN7484
9Sp SN74196 LI .60
40p SN7407
36p 5547485 LI 00 5N74197 [I .58
40p SN7408
19p 5N7486
29p SN74198 LI .BO
38p SN7409
I8p SN7490
42p SN74199 11 40
LI 05 SN7410
16p SN7491
75p SN76003N12.92
SN741 I
20p SN7492
45p SN76013N11.95
44p 5N7412
22p SN7493
45p SN76023NL1.60
[I
LI.06MC1330P
CD4037
Scientific notation. Display shows
015800670
45p NE555V
70p SN7442
45p NE556 LI 30 SN7446
LI 25 NE560 14 48 SN7447
LI .94 NE565 E4 48 SN7448
LI 25SL414 [2 35SN7450
[I.995N7425
43pMC1303LLI.505N7427
83p MCI 310P [2.50 SN7430
CD4027
CD4028
CD4029
CD4030
Antilogi o, giving quick access to xy
(including square and other roots).
01-6360845
18pLM7812
72p LM7815
19p LM7824
C834025
Sin and Arcsin. Cos and
and Arctan. Automatic squaring.
Automatic doubling. log) o and
0/6362605
BOIL
98p
14DIL
88p LM3900
85p'LM7805
CD4022
CD4023
CD4024
-, x
Arccos. Tan
01.6372232
Sip
CD4021
SCIENTIFIC
Functions summary Four
arithmeticfunctions: ( +,
LONDON
10Tottenham Court Road, WI.
33 Tottenham Court Road, WI.
42 Tottenham Court Road, WI
257 Tottenham Court Road, WI
88p LM748
CD4019
CD4020
FEATURES OF THE SINCLAIR
Oxford Street, WI. 01- 4938641
TO99
BDIL
14DIL
18p LM710
18p LM723C
4Sp LM741C
89p TO99
89p RDIL
4Sp
14DIL
88p L54747
S2p
S2p
CD4011
CD4012
CD4013
CD4014
CD4015
CD4016
complete step -bystep instructions.
Assembly time is
about 3 hours.
The Sinclair
Scientific performs logs,
trigs and arithmetic at the
touch of a button.
LM709
18p
82p
CD40I0
-
401
99p LM702C
CD4006
CD4007
CD4008
CD4009
Britain
SN74151
611p
6Sp SN74153
6Bp
84p SN74154 LI .10
80p SN74157
76p
90p SN74160
BBp
I
OEE
2M3771C220
2N3773L1.65
2N3789 12-06
2N3819 37p
2N3820 19p
2N3904 19p
2N3906
19p
42p
2N4036 67p
2N4058 I8p
2N4062 ISp
2N4289 34p
2N4920L1-10
21,44037
2N4921 83p
254492311-00
2N5245 29p
2N5294 48p
2N5296 48p
2N5457 29p
2N5458 26p
2N5459 29p
2N6027 45p
73p
3N128
3N140 LI -00
3N141
81p
3N200 L249
40361
40p
40362
40406
40407
40408
40409
40410
40411
40594
40595
40636
40673
ACI62
ACI27
AC128
AC151
4Sp
44p
35p
50p
Sip
51p
[2-00
74p
84p
LI10
73p
20p
40p
35p
27p
AC152 49p
ACI53
SSp
AC176
4Ip
AC187K Up
ACIB8K 40p
68p
AD143
AD161
ADI62
AFI06
AF109
AFIIS
AFI 16
AFI 17
AFI18
AF124
Prices correct
69p
69p
40p
40p
35p
35p
35p
3Sp
30p
atApriil,
AF139
AF239
AF240
AF279
65p
65p
90p
70p
AF280
AL102
BC107
BC108
BC109
BCI47B
[I
79p
IIp
I6p
BC158A
BCI68B
BC16981
BCI82
BC183L
BCI84L
BC212A
16p
BC2I2LA 16p
BC2I3LA ISp
BC2I4LB Itp
8C2378 16p
BC238C
BC239C
BC257A
ISp
ISp
16p
16p
17p
34p
BC307B 17p
BC308A ISp
BC309C lOp
BC327
23p
BC328
21p
BCY70
17p
BCY71
21p
BCY72
18p
LI-00
BD132
50135
3
BD136
BD137
B
1976,
BF194
,
BFI95
BFI96
BF197
ISp
I3p
I3p
BC 184
BD121
BD123
BD124
B0131
BF 184
BF244
BF2S7
BF258
BF259
lip
12p
lip
BCI83
BC258B
BC259B
BC301
BFIBI
BFI98
12p
13C182L
SSp
16p
Ibp
I5p
BCI6713
BF117
BF180
9p
BC149B
BC157A
71p
BFIS4
BFI59
-00
14p
14p
14p
IOp
BCI48B
BD139
BD140
BFI I5
82p
67p
40p
50p
2Ip
22p
24p
26p
BF561
BF598
B7p
291p
20p
27p
35p
36p
30p
Ilp
12p
13p
1Sp
I8p
2Ip
47p
S3p
55p
27p
23p
14p
24p
32p
34p
30p
BFR39
BFR79
BFX29
BFX30
BFX84
BFX85
35p
BFXBB
30p
BFY50
10p
BFYSI
28p
BFY52 10{p
BRY39
48p
ME0402 20p
ME0412 IBp
ME4102 I I p
M1480
95p
Mj481
LI-30
Mj490
[I-OS
MPSA56 31p
0C28 LI .4B
0C35 LI 16
0C42
SOp
0C45
32p
TIP29A
TIP29C
TIP31A
TIP32A
TIP33A
TIP34A
TIP35A
TIP36A
49p
80p
62p
74p
[IOI
LI .51
L2-90
TIP42A
TIP2955
TIP3055
98p
TIP4IA
T1S13
ZTX300
ZTX301
ZTX500
ZTX501
ZTX502
N914
N3754
N4007
N4148
N5404
N5408
AA119
BAI02
BAI 45
BAI54
13.70
79p
90p
SOp
IBp
13p
I3p
ISp
I3p
l8p
3}p
15p
IOp
4p
lip
30p
Sp
ISp
ISP
BAI55
12p
12p
27p
BBIO4B
BY126
45p
12p
BBI03B
Mj491
1.45
Mj2955 LI -00
M1E340
48p
BYI27
BYZ11
Sip
SIp
MIE371
MJE520
OA81
OA90
1Bp
BY164
57p
TIC44
C1060
19p
MjE370
M
M
65p
75p
60p
70p
E2955L1.20
E3055
MP8113
MPFI02
75p
47p
39p
MPSAOS
2Sp
MPSA06 319
NPSA55 1Ip
but all exclusive of VAT
BYZI2
0A47
0A91
0A200
15p
6p
6p
Op
Bp
ST2diac 20p
40669 1I.00
6Sp
ORP12
60p
P, &P.25p
BBBBBI
Practical Wireless, May 1976
WILMSLOW AUDIO
THE
Firm for speakers!
Group 25, 3, 8 or 15 ohms
Group 35. 3, 8 or 15 ohms
Group 50/12 8 or 15 ohms
Group 50/15 8 or 15 ohms
Deluxe I2" 8 or 15 ohms
Major 3, 8 or 15 ohms
Superb 8 or 15 ohms
Baker Regent 12" 8 or 15 ohms
Baker Auditorium 12" 8 or 15 ohms
Baker Auditorium 15" 8 or 15 ohms
Celestlon G12M 8 or 15 ohms
Celestion G12H 8 or 15 ohms
Celestion G12/50 8 or 15 ohms
Celestlon G12/50TC 8 or 15 ohms
Celestlon GI 5C 8 or 15 ohms
Celestion G18C 8 or 15 ohms
Celestlon HF1300 8 or 15 ohms
Celestion HF2000 8 ohms
Celestion MH1000 8 or 15 ohms
Celestion CO3K
Decca London ribbon horn
Decca London CO /1000/8 Xover
Decca DK30 ribbon horn
Decca CO /1 /8 Xover (DK30)
EMI 14 x 9 Base 8 ohms 14A770
EMI 8 a 5, 10 watt, d /cone, roll sur,.
EMI 6)" d /cone, roll surr. 8 ohms
EMI 8 roll surr. bass
EMI 5' mid range
Eiac 59RM109 (15) 59RM114 (8)
Elac 64" d /cone, roll surr. 8 ohms
Elac 10" 10RM239 8 ohms
Eagle Crossover 3000hz 3, 8 or 15 ohm
Eagle FR4
Eagle FR65
Eagle FR8
Eagle FR10
Eagle HT15
Eagle HT21
Eagle MHTIO
Eagle FF28 multicell. horn
Fane Pop 15, 8 or 16 ohm
Fane Pop 25T, 8 or 16 ohm
Fane Pop 33T, 8 or 18 ohm
Fane Pop 50, 8 or 16 ohm
Fane Pop 55, 8 or 16 ohm
Fane Pop 60, 8 or 16 ohm
Fane Pop 70, 8 or 16 ohm
Fane Pop 100, 8 or 16 ohm
Fane Crescendo 12A, 8 or 16 ohms
Fane Crescendo 12BL, 8 or 16 ohms
Fane Crescendo 15/100A, 8 or 16 ohms
Fane Crescendo 15/125, 8 or 16 ohms
Fane Crescendo 18, 8 or 16 ohms
Fane 910 Mk II horn
Fane 920 Mk 11 horn
Fane HPX1 crossover 200 watt
Fane 13 x 8, 15 watt dual cone
Fane BOIT 8" d /c, roll surr.
Goodmans Axent 100
Goodmans Audiom 10015 ohm
Goodmans Audiom 200 8 ohm
Goodmans Axiom 402 8 or 15 ohm
Goodmans Twlnaxiom 8, 8 or 15 ohm
Goodman, Twinaxiom 10, 8 or 15 ohm
Goodmans 8P 8 or 15 ohm
Goodmans 10P 8 or 15 ohm
Goodmans 12P 8 or 15 ohm
Goodmans 12PG 8 or 15 ohm
Goodmans 12PD 8 or 15 ohm
SPEAKER KITS
SPEAKERS
SPEAKERS
Baker
Baker
Baker
Baker
Baker
Baker
Baker
4061
E19-25
E11-N
E70-62
E13-7S
E1107
EU12
4IS-N
LI{-2S
£21-S{
£12-OS
EIS-95
E/6-S0
E16N
E26-93
E31-N
47-75
LO-SO
£13-S0
E/-MS
E32-N
E7-S0
E1O-N
ES-06
E13-23
E393
E/-37
E037
E3-S0
L3-75
E1-25
E393
E1-73
L6-12
EO-62
E12-31
£18-62
E/N
E6t1
E4-44
40N
F4-23
E7-S0
Et-75
L12-50
£15 50
E17-25
EIS 7S
127-03
£37-73
136- S0
£49- 93
ES7
OS
E67-SS
£1/-9S
E33-OS
E2-S0
ES-50
£9-N
E6-M
E13
N
£I1-0S
£22-60
E16-SS
E10-93
ES-93
£6-25
E14-116
E10-S0
L16-95
Goodman, I2AX
E3{.S{
or 15 ohm
Goodmans 15AX or 15 ohm
Goodman, 15P 8 or 15 ohm
Goodman, 18P 8 or 15 ohm
Goodmans Max 750P
Goodmans 5" midrange 8 ohm
Gauss 12" 200 watt
Gauss 15" 200 watt
Gauss 18" 200 watt
Jordan Watts Module 4,8 or 15 ohm
Kef
Kef
Kef
Kef
Kef
Kef
Kef
Kef
8
8
140.110
£22-N
E30-N
E16.60
E6-SO
E73.6{
fs3-N
£11{-N
E17-N
ES- 75
LO -N
T27
T15
Allan
Allan
Allan
Allan
Richard Allan
Richard Allan
Richard
Richard
Richard
Richard
Triple
Triple
8
12
Super Triple
RA8 Kit
RA82 Kit
RA82L Kit
each
each
each
each
each
£S{N
each
E11-SO
E14-16
E22-SI
£27.93
E32-S0
pair E12-N
pair EN -N
pair E73-N
Fane Mode One Mkt
Wharfedale Linton II kit
pair E23.12
pair ES3-N
pair LN-N
Wharfedale Glendale 3XP kit
Wharfedale Dovedale Ill kit
ET- SO
13110
LS-70
E10TS
B200
8139
DNB
DN12
DN73 SP1015 or SP1017
Lowther PM6
Lowther PM6 Mk 1
Lowther PM7
E2-31
£S-N
EA-SO
E27-S0
F29-95
14140
Peerless KOIODT t or 8 ohms
Peerless DTIOHFC 8 ohms
Peerless KOIOMRF 8 ohms
Peerless MT225HFC 8 ohms
Richard Allan CA12 12" bass
Richard Allen HP8B
Richard Allan LP8B
Richard Allan DT20
Richard Allan CN8280
Richard Allan CN820
Richard Allan Super disco 80W 12"
Richard Allen CG15 15" bass
Richard Allen Super Disco 10' 50 watt
Richard Allen Super Disco 8' 50 watt
Radford BD25
Radford MD9
Radford MI36 dome mid range
Radford TD 3
Redford Crossover network
El- OE
ES-III
E10-31
E3-12
£22-N
E13ßS
Et- 25
46.75
LIS-N
E3-S0
E16-93
EN-SO
E13-2$
L12-93
Ett-M
E11 -SO
E12-S0
STC 4001G
Tannoy 10" HPD
Tannoy 12" HPD
Tannoy 15" HPD
/DD
8
Akai, Armstrong, Bowers & Wilkins,
Castle, Celestion, Dual, Goodmans,
Kef, Leak, Pioneer, Radford, Richard
Allan, Rotel, Tandberg, Trio, Videotone
Wharfedale etc. -Ask for our HIFI
price list !
E6-0{
1375-00
10 RS
HI -FI
ON DEMONSTRATION
in our showrooms
E14-23
E20-33
E0-S0
BD25 Mk II
Wharfedale Super
Castle 8 RS/DD
Peerless 1120
Richard Allan Twin assembly
E81-93
£07-93
ohms
LIS- KO
L10-31
Complete RADFORD range In stock,
Amplifiers, Preamps, power amps,
low distortion oscillator, distortion
measuring set etc.
SPEAKER KITS
Baker Major Module 3,
8 or 15 ohms
Goodmans DIN 20 4 or 8 ohms
Goodmans Mezzo Twin Kit
Heime XLK 20
Helme XLK 30
Helme XLK 35
Helme XLK 40
Helme XLK 50
KEF kit 1
KEF kit III
Peerless 20-2
Peerless 30-2
Peerless 20-3
Peerless 50-4
Peerless 3-15
Peerless 1060
Peerless 1070
each
each
pair
pair
pair
pair
pair
pair
pair
each
each
each
each
each
each
pair
each
E1/-7S
E11-7S
E17-10
EIS-60
All items guaranteed new and perfect.
EION
EM-N
Prompt despatch.
E5{-N
PRICES INCLUDE V.A.T.
CORRECT AT 26.2.76
£35-00
£S3-N
E10-N
EI7-M
1E24-38
E26-S{
Es0-S0
Carriage:
E17-1O
ES{N
£46- Of
&
ARE
Sap per speaker. (12" and over 73p each)
Tweeters, crossovers 30p each
Kits Np each (LI -N pair)
Send stamp for tree booklet "Choosing
speaker ".
COMPLETE KITS IN STOCK FOR RADFORD STUDIO 90,
MONITOR 180, STUDIO 270, STUDIO 360, HIFI ANSWERS
MONITOR, HIFI NEWS NO- COMPROMISE, WIRELESS
WORLD TRANSMISSION LINE, PRACTICAL HIFI AND
AUDIO (GILES) MONITOR ETC.
WILMSLOW
AUDIO
Construction leaflets for Radford, Kef, Jordan Watts, Tannoy etc. free on
request.
Loudspeakers: Swan Works. Bank
Square, Wilmslow, Cheshire P.A.,
HiFi etc: 10 Swan St. Wilmslow.
HIFI, Radio ate: Swift of Wilmslow, S Swan
P.A. Amplifiers, microphones etc. by Linear, Shure, Eagle,
Beyer, AKG etc.
Dept. PW
St.
Wilmslow.
(speakers)
FREE
with orders over £10 -"HiFi Loudspeakers Enclosures" Book
Practical Wireless, May 1976
28213
Telephone
(HIFI etc)
Wilmslow
29309
R
C
*
INCORPORATING A GARRARD DECK
STEREO
Garrard 3 speed Deck automatic, manual
facilities together with stereo cartridge and
cueing device.
Stereo 21, easy to assemble audio system kit. No soldering required.
The unit is finished in Sim Teak and the acrylic top presents an
unusually interesting variation on the modern deck plinth.
Includes - 3 speed deck, automatic manual facilities together
with stereo cartridge and cueing device.
.
ELIZABETHAN STEREO TUNER AMPLIFIER
This compact Tuner Amplifier
gives you full medium wave
and V.H.F. coverage and FM
stereo. With inputs for your
turntable and tape recorder.
It has rotary tuning. Volume.
Balance. Bass and Treble
controls and push button
tQ'
selection switches for Phona/tape FM
Stereo, FM mono Medium wave and A.F.C. has built -in
stereo beacon and switched headphone socket.
Technical Specifications 15 transistors. 11 diodes, integrated circuit.
Power output 8 watts. Size of tuner amplifier: 4"x 10' "x 15} approx.
Finished in selected rosewood veneer with brushed aluminium iront
panel and matching controls. Output into 15 ohms speakers only.
-
-`
I
-`
£29.00
+ p&p £1.50
COMPLETE ONLY
£23.20 +
p
&p £4.00
Two speakers with cabinets.
Amplifier module. Ready built with control panel, speaker leads
and f ull. easy to follow assembly instructions.
Specifications- For the technically minded.
Input sensitivity 600mV. Aux. input sensitivity 120mV. Power
output 2.7 watts per channel. Output impedance 8-15 ohms.
Stereo headphone socket with automatic speaker cutout.
Provision for auxiliary inputs - radio, tape, etc., and outputs for
taping discs.
Overall Dimensions. Speakers approx 12 "x 9 "x 5 Complete
deck and cover in closed position approx. 15 k x12 k6:
Extras if required. Optional Diamond Styli £1.80.
Specially selected pair of stereo headphones with individual level
controls and padded earpieces to give optimum performance f5.80
BSR DECKS WITH PLINTHS AT EASY TO BUILD SPEAKER KITS
FANTASTIC REDUCTIONS
MP 60 Type (illustrated)
Less Cartridge
C141 (not illustrated)
£16.00
p &p
£2 00
£12.00
Auto. with Cue
p &p £.1- 50
Fitted Stereo Cartridge
All plinths finished in matching Teak veneer.
THE`COMPACT'
These superb simulated teak -finished speaker kits have been specially
designed by RT -VC for the cost -conscious hi -fi enthusiast who wants
top quality speakers but doesn't want to spend the earth. Built to EMI's
exacting specification. these new RT -VC speaker kits (350 type kit)
incorporate 13 08 woofer, 3;tweeter and matching crossover.
Easily put together with just a few basic tools.
Specification leach speaker): Impedance 8 ohms. Power handling
15 watts RMS (30 watts peak). Response 20- 20.000 Hz. Size
20 x 11 "x 91" approx. Comparable built units (EMI LE3) sold elsewhere
for over £45 pair.
Complete with crossover
Component s and circuit
£22.00
P air complete
+ £5.20
p
SPEAKER KIT
&p
bookshelf speaker system giving a high electro
accoustic efficiency for the low powered amplifier.
The professional finish can be obtained with the minimum of
tools, the infinite baffle type enclosures come ready mitred and
professionally finished, and fix together with masking tape till
glue dries.
The cabinet measures 12" o 9" x 5 deep approx finished in
simulated teak, incorporating a quality 7 "x4 elliptical speaker,
power handling 4 watts, flux density 30.000 maxwells,
p &p £1.70
impedance 8 -15 ohms nominal, voice coil dia ,i magnet size
2s approx.
PAIR INCLUSIVE
diagram.
A compact
EMI 350 KIT
£7.25 +£1.2Op&p.
Complete with crossover
Components and circuit
diagram
£6.00+
System consists of a 13" x 8"
approx. woofer with a 3"' tweeter,
crossover components and circuit
diagram. Frequency response: 20 Hz
to 20 KHz. Power handling 15 watts
RMS into 8 ohms. (Peak 30 watts.)
VISCOUNT IV STEREO AMP
RMS
WATTS
£27.50
£1.50
+
COMPLETE 20x20 SYSTEMS
p
£69.00
+ 20 watt Stereo Amplifier
&p
SYSTEM 1A
incorporating the latest silicon transistor solid state circuitry, the
The new 20
RT -VC VISCOUNT IV gives you a powerful 20 watts RMS per channel into 8 ohms. Superb teak -finished
cabinet, with anodised fascia to harmonise with any decor. Polished trim and knobs.
The VISCOUNT IV has a comprehensive range of controls -volume. bass, treble, balance mono /stereo, mode
selector, and scratch filter.
Front panel socket for stereo headphones. And a host of sockets at the rear - for left and right speakers, tape
recorder, auxiliary , tuner, disc and microphone.
SPECIFICATION: 20 watts RMS per channel 40 watts peak. Suitable 8-15 ohms speakers.Total distortion at
10 watts better than 0.2 %. Six switched inputs:1. Magnetic PU. -3 millivolts at 47 K ohms (R.I.A.A.). 2. Crystal/
ceramic P.U. - 50 millivolts at 50 K ohms (R.I.AA.); 3, 4, 6. Tape Tuner /Aux. -140 millivolts at 50 K ohms (flat
frequency response); 5. Microphone -3 millivolts at 50 K ohms (flat frequency response).
CONTROLS: Push button ON /OFF, stereo /mono, scratch filter. 6 position rotary selector. Individual rotary
controls for treble. bass, balance and volume. Headphone socket, tape out socket. Aux.
mains output. Frequency response: 25 Hz to 25 kHz at full rated output. Signal to noise
ratio: better than -50 dB on all inputs. Tone control range: Bass ±15 dB at 50 Hz; Complete System
with these speakers
Treble ±12 dB at 10 KHz. Power requirements: 250V A.C. mains at 80 watts.
Approx size:151 "x 3 "x 10: MP60 type deck with magnetic cartridge. de luxe plinth and
in
cover. Two Duo Type lia matched speakers - Enclosure size approx. 191" x 10:" x 7
+ £6.50 p &p.
in simulated teak. Drive unit 13 "x8 with 3' tweeter.15 watts handling. 30 watts peak.
20x
SYST
£69.00
SYSTEM 2
£85.00
'Viscount IV amplifier (As System
1
al
M P60 type deck (As System al
Two Duo Type Ill matched packers
Enclosure size approx. 27" x 13'
x 11 } ". Finished in teak simulate.
Drive units 13" x 8' bass driver, and
two 3" (approx.) tweeters. 20 watts
RMS. 8 ohms frequency range
20 Hz to 18.000 Hz.
Complete System with these _
1
-
-
4icsakera
14
£85,0D
+f1.60
p
& p.
I.
PRICES: SYSTEM
Viscount IV R103
amplifier
£27.50 +11.90
2
PRICES: SYSTEM
IV R103
6
p.
(30.00. £6.50 p 6
p.
p
Duo Type Ha
speakers
2
MPS() type deck with Mag, cartridge
de luxe
plinth
and cover
f22.00. f3.30p&p.
Total if purchased
£79.50
Available maples for only:.£69
+£6.50 p 6
sparataly:
Viscount
amplifier
Duo Type III
£46.00 +f 7.50 p 6 p.
MP60 type deck with Map. cartridge
deluxe plinth
and cover
£22.00af3.30p &p.
Total repurchased
speakers
savant*:
00
p.
2
£27.50.11.90 p&p
ilmrlIllk,/,/,
r
£95.50
Amdahl. templet. for only
£85.00
£762 p6
p.
Scotland and the Orkneys P & P Surcharge
System a £1.75 System 2 13.50
1
Note: 30 x30 kit available
only as a separate item.
Prac7ical II ircles.s, May 1976
PUSH BUTTON CAR RADIO KIT- 'Pali BUTTON CAR RIND +fl.05&
Easy to assemble construction kit comprising fully
completed and tested printed circuit board on
THE TOURIST TT*
is required. All connections are
no
p
-
f
V
I,'^ "r
...Ji1
-tj
which
soldering
simple push fit type making for easy assembly.
Fine tuning push button mechanism is fully built
and tested to mate with printed circuit board.
Speaker including baffle and fixing strip £2.00
fully
+45p p & p. Car Aerial Recommended
-
retractable f1.60 +40p p & p.
The Tourist I Kit For the experienced constructor.
If you can solder on a printed circuit board you
can build this model. Same technical specification
as Tourist TT.
Price
+fl.05 p & p.
f8.20
TECHNICAL SPECIFICATION: (1) Output
4 watts RMS output. For 12 volt operation on
negative or positive earth. (2) Integrated circuit
output stage, pre -built three stage IF Module.
Controls volume manual tuning and five push
I Kit, same specification as
complete with speakers. fume
kit and fully re+s &o
Jinn C 50
tractable aerial
The Tourist
Tourist
buttons for station selection, illuminated tuning
scale covering full. medium and long wave bands.
Size chassis 7" wide 2" high and 41` deep approx.
NO SOLDERING REQUIRED
TT
I
STEREO CASSETTE
TAPE DECK KITS
Kit comprises of ready built cassette tape
transport mechanism. Featuring pause
control. solenoid assisted auto -stop.
3 digit tape counter, belt- driven balanced
fly wheel,DC motor with electronic speed
control, ready built and mounted record/
replay PC board, and two VU meters. power supply.
PC board.mains transformer. Input and output
sockets and two level controls. Specification power
source 240 AC 50Hz. Output more than 0.5v impur
Reliant Mk IV Mono Amplifier, ideal for the small
disco or house parties. Output 20 watts RMS into
8 ohms (suitable for 15 ohms).
Inputs
individual
electrically mixed inputs.
mixing controls. Separate bass and treble controls
common to all 4 inputs. 'Mixer employing F.E.T.
Solid State circuitry.
(Field Effect Transistors).
'4
mike -65dB.10KS2. DIN -47dB.100KQ.Track
system 2 channel stereo record play -back.Tape
speed.4.8CM /SEC. Frequency response 50- 12.00Hz signal
to noise ratio
42dB. Recording system AC Bias. Erasing
system AC erase. Bias frequency 57KHz.Size of mechanism
8" x 5" x 3'/2" approx: unit easy to mount into your cabinet
3" required to clear
This is an advanced kit
base of mechanism
not suitable for those
approx.
-
without electrical
knowledge and those
+ pbp f1.50
unable to solder.
complete details.
8 TRACK HOME
CARTRIDGE PLAYER
\_
p
&
p.
121,x6"x31'
tleg ant self selector push button player
use with your stereo system.
fo
Compatible with Viscount IV system,
Unisound module and the Stereo 21
Technical specification
Mains input,
125mV.
240V,
Output
sensitivity
-
Also available with
2
speakers
(7'x4')
fill
I
f1.75
DO NOT SEND CARD
Just write your order giving
your credit card number
subject to change without notice.
Minimum order on ACCESS /BARCLAYCARD--f 11.
Practical Wireless, May 1976
-
p
& p.
£8,95
f1.05
R
p & p.
f7p &p
INCORPORATES Pre -Amp with full mixing facilities, including switched input
for mic with volumé control, switched input for auxiliary with volume control,
bass and treble controls. Volume control and blend control for turntables. Two
B.S.R. MP60 type single play professional series decks, fitted with crystal cartridges.
TECHNICAL SPECIFICATION:
Pre-amp
Output
200mV.
Auxiliary
inputs
200mV and
750mV into
map Mic input
6mV
into
100K.
240 volt operation.
Turntables capacity
7 ", 10" or
12" records. Rumble wow and flutter
Rumble Better than -35dB. Wow
Better than 0.2 %. Flutter Better than
Console size
-
-
Unit
.
-
Closed-171"x 131" x B1" (app)
351 x131- x 41" (app.)
Unit Open
-
0.06% ( Gaumont kalee meter).
Finish
Satin black mainplate with
turntable mat inlaid with
black
brushed aluminium trim. Tonearm and
in
controls
black
and- brushed
aluminium.
All prices include VAT at current rates
Acc..
&
- here's
Also available with the 'Compact' (see opposite page) easy build speaker kitf13.5D -f
-
w,
p
high efficiency I.C. monolithic pbwer chips which ensure
very low distortion over the audio spectrum. 240V. AC only.
-
an o.
+f1.35
your chance to start, with Unisound
pre -amp, power
amplifier and control panel. No soldering just simply
screw together. 4 watts per channel into 8 ohms. Inputs:
120mV (for ceramic cartridge). The heart of Unisound is
1
stamped addressed envelope. Goods not despatched
outside U.K.
ÍLeaflets available for all items listed thustend
stamped addressed envelope. All items subject to
availability. Prices correct at 1st Mar. 1976 and
-
For the man who wants to design his own stereo
-
Mail orders to Acton. Terms C.W.O. All enquiries
£20.00
-
BUILD YOUR OWN STEREO AMPLIFIER*
r
PORTABLE DISCO CONSOLE*
!
-
-
SPECIAL OFFER
+fl.70
-
INPUT SENSITIVITIES
Input
1). Crystal mic.
guitar or moving coil mic, 2 and 10mV. (Selector
for
Inputs
2). 3), 4).
switch
desired sensitivity.)
Medium output equipment
ceramic cartridge,
tuner, tape recorder, organs, etc.
all 250mV
sensitivity. AC Mains, 240V operation. Size approx:
As above
Yours
for only
£14.00
'Attractive styling.
for
or send SAE
but complete with build
yourself Unisound Amplifier Kit
(see opposite cant) + 2 'Compact'
easy to
build
7G`W. W
7[.
speaker kits (see
opposite page)
+ o & p 02.00
'3
-
This disco console is ideally matched
for the Reliant IV and Disco 50 or any
other quality amplifier.
The unit is finished in black PVC with
contrasting simulated teak edging.
diamond spun control knobs with
matching control panel.
Yours for only
£49.00
+f6.50p &p.
C
HIGH STREET, ACTON, LONDON W3 6NG
323 EDGWARE -ROAD, LONDON W2
21 C
Personal Shoppers EDGWARE RD: 9 a.m.- 5.30p.m. Half day Thurs
ACTON: 9.30a.m. -5p.m. Closed all day Wed.
i
15
LYNX ELECTRONICS
Translators
AC126
AC727
25p
10p
BC183
BC183L
BC184
BC184L
BC207B
BC212
BC212L
BC213
BC213L
BC214
BC214L
BC237
BC238
BC300
2Sp
BC301
Sip
BC323
BC327
BC328
BC337
BC338
15p
lip
13p
AC128
AC128K 25p
AC141
tip
AC141K 21p
lip
AC142
ACt42K Zip
AC176
AC176K
AC187
AC187K
AC188
AC188K
AD140
AD142
AD143
AD149
AD761
AD162
AL102
AL103
AF114
AF115
AF116
AF117
AF118
AF139
AF239
16p
25p
lip
SOP
Up
45p
35p
359
95p
93p
20p
20p
29p
BCI53
BC157
BC158
BC159
BC160
BC161
BC168B
BC182
BC182L
16p
16p
34p
32p
60p
12p
12p
36p
40p
60135
36p
39p
40p
SSp
dip
139136
UV
lop
lop
BD131
BD132
B0137
BC126
BC126
BC141
BC742
BC143
BC111
BC147
BC148
BC149
BC152
BCt25
12p
12p
BCY72
B0115
33p
lop
1/p
lop
Bolso
Sip
12p
11p
BCY71
SOp
BC107
BC107B
BC108
BC109
BC109C
1lp
18p
16p
17p
17p
BCY70
20P
10p
10p
11p
BD139
Op
6Sp
92p
00182
80184
970
B0184 E1.20
OOp
P0231
BD231
OOp
00p
B0232
OOp
BD233
OOp
139237
BD781
16p
139
14p
10p
10p
20p
Zip
23p
23p
30p
80238
9p
Op
9p
25p
lip.
9p
9p
9p
32p
Sip
9p
11p
11p
BF257
BF258
8E337
30p
35p
32p
BFW60
17p
BFX29
BFX30
BFX84
BFX85
BFX88
BFY50
26p
30p
23p
BFY51
BFY52
BFY64
BFY90
BRIO)
BRY39
BSX19
BSX20
17p
MJE340
40p
16P
MJE371
80p
45p
MJ480
sop
£105
MJ481
MJ490
90p
MJ491
£7.15
MJE520
MJE521
0A5
SSp
50p
2N696
2N697
2N706
2N929
2N930
14p
12p
10P
2N1131
15p
16p
20p
20p
Up
Up
2N1132
2N1304
2N1305
2N1711
2N2102
2N2369
2N2369A
2N2484
2N2946
2N2905
2N2905A
2N2926R
2N29260
lip
44p
14p
14p
16p
SOp
18p
22p
10p
9p
9p
BYX36-300
SC4OB
SC400
98p
BYX38-600
SC4OF
BYX36-900
SC4ID
65p
70p
05p
BSp
BYX36-1200
SC11D
SC41F
ST2
2N3771 E1 60
600
900
C1085
C706D
10p
ISp
SC41A
21p
22p
lOp
73p
dlp
60p
20p
44p
50p
TIP29A
TIP30A
55p
TIP32A
54p
64p
N2069
N2070
lop
16p
Ti P31A
S2p
TIP34 El.05
TIP41A 68p
TIP42A 72p
80 D
zeners 20p
BZX83 or
BZY88 series
zeners
Cl 06A
1Op
SC40A
series
BZX61
15p
15p
12p
0072
0084
BSp
1200
OC41
OC71
BYX38-
BYX38-
Op
Op
OC44
OC45
OC70
1tp
BYX38-
OA90
0A91
0C42
129
05p
300
ISp
20p
20p
18p
19p
35p
65p
20p
40p
CRS3 -20 50p
CRS3 -40 60p
CRS3 -60 85p
E1.90
BU126 E1-00
159
BY206
BY207
20p
BYX38-
10p
10p
12p
12p
CRS3 -10 ISp
02
00p
30P
25p
LTD
2N2926Y
2N2926G 10p
15p
2N3053
40p
2N3054
2N3055
50p
56p
2N3440
20
2N3442
2N3570
60p
10p
2N3702
2N3703
10p
10P
2N3704
10p
2N3705
lOp
2N3706
10p
2N3707
2N3714 £1.15
2N3716 El- 5
2N377í E1.60
OOp
BF194
BF195
BF196
BF197
BF224J
BF244
CRS3 -05 34p
tap
80p
60p
60p
65p
55p
20p
BF178
BF179
35p
25p
25p
35p
40p
CRS) -60 6Sp
20p
BSY95A 12p
BT106 £1.00
BT107 E7 .60
BT108 L1.60
BT109 LI-00
BT116 £1.00
BU105 El .$0.
BU105/
BDY20
BDY38
BDY60
BMW
C106F
CRS1 -05
CRS1 -10
CRS1 -20
CRS1 -40
BSX21
BD239
BDY61
(LONDON)
N4001
N4002
N4003
N4004
N4005
N4006
N4007
11p
40p
45p
50p
4p
Sp.
Bp
7p
Op*
9p
10p
LI
2N3772 LS-10
2N3773 ES-1p
2N3819 2tp
2N3904 16p
2N3906 16p
2N4124 14p
2N4290 1213
2N4348 El.20
2N4870 35p
2N4871
2N4919
2N4920
2N4922
2N4923
2N5060
2N5061
2N5062
2N5064
35p
70p
50p
511p
64p'
20p
ISp
27p
30p
NATIONAL CLOCK CHIPS
E525.a
MM5314 £375. MM5316
DIGITAL DISPLAYS & LED's
DL7
DL750
99p
99p
DL707
DL707
THYRISTORS
8A
50
100
lA
YELLOW
6A
(T0220)
3A
(7092)
(T05)
(C106 type)
20
25
27
30
25
25
35
40
35
40
45
50
41
85
70
1.09
200
400
600
the good components service
In relatively few years, Electrovalue has risen to a position
of pre- eminence as mail -order (and industrial) suppliers of
semi -conductors, components, accessories, etc. There are
wide ranges and large stocks to choose from as well as
many worthwhile advantages to enjoy when you order
from Electrovalue.
CATALOGUE 8 -ISSUE 2
With the first printing sold out, Issue No. 215 up -dated on prices,
etc. 144 pages. New Items. Opto-electronics. Diagrams of components, applications. I.C. circuits, etc. Post tree 10p, including
voucher for Np for spending on order over £5 list value.
/
On all C.W.O. mall orders, except for some items marked NETT.
50/0 on orders Ilst value
1 0 on orders Ilst value
0
£15 or more
£10 or more
FREE POST & PACKING
On all C.W.O. mall orders in U.K. over £2
add 15p handling charge.
Prices are held and then reviewed over minimum periods of
months -Next price review due April 10 1978.
QUALITY GUARANTEE
everything In our Catalogue -No manufacturer's relicts,
seconds or sub -standard mrthandl;e.
On
(a)
(T0220)
(T0220)
(TO220)
42
48
60
47
6
54
68
70
90
96
1.10
1.50
47
s8
87
8.5A
4A
0.60
0.64
0.77
0.98
100 V
200 V
400 V
800 y
u
1.19
ELECTRO ALUS LTD
to Dept. 511, 28,
ST. JUDES ROAD, ENGLEFIELD
GREEN, EGHAM, SURREY TW20 SUB. Telephone Egham 3603, Telex
284475. Shop hours 9-5.30 dal /y, 9-1 pm Sats.
686,
1.26
(b)
(a)
0.80
0.64
0.76
0.70
0.75
(h)
070
10A
O-SA
(a)
(b)
0.78
0.67
0.97
(a)
1SA
(a)
(b)
1.01 1.01
(b)
063 0.03
0.78
0.07
0.87 0.87
1.17 1.17
0.75
1.01
1.13 1-19
1.70 1.74
000 003
099 0.67 1-01 1-21 1ß6 1.42 1-50 2.11 2.17
N.B. Triaca without Internal trigger diac are priced under column (a).Trlacs with
Internal trigger diac are priced under column (b). When ordering please indicate
clearly the type required.
TTL
74
mixed prices
100+
-24
14p
14p
25 -99
12p
12p
lOP
10p
7402
7403
7404
7408
7409
14p
12p
1Op
lop
13p
13p
17p
741,9
16p
131
1
7400
7401
12 }p
15p
16p
18p
lop
7413
7417
7420
7427
7430
7432
7437
27p
16p
27p
27p
27p
75p
65p
7441
7442
11p
lip
lip
20p
11p
tap
176p
75p
7447A 95p
7470 30p
7472
25p
7473
25p
7474
32p
32p
7475
7476
32p
7482
75p
7485 Et .30
32p
7486
lIp
22 }p
22=,p
13p
22 }p
22 }p
lop
62p
50p
43p
11p
lip
itp
SSp
-24
55p
55p
1
7445
7447
7448
10p
11p
13p
7489 £2.92
7490
49p
7491
BSp
25-99 100+
71p
57p
71p
57p
75p
15p
$3p
87p
25p
20p
21p
17p
259
17p
2Sp
21p
26p
21p
26p
21p
62p
50p
E1.09
87p
Zip
21p
£2.80 E2-10
40p
32p
55p
ISp
1
-24
25-99 100+
Slp
ISp
7492
7492
7495
45p
74100E1.05
74107 35p
74121.34p
SBp
40p
40p
89p
32p
32p
72p
72p
23p
31p
31p
2tp
2Sp
SOP
Up
74122 34p
dip
74121
4SD
74145 71p
74154 E1.62
74174 E1 -00
LI.48
74180£106
Up
74181 E3 20
74192 E7 .35
lip
03p
86p
67p
71p
63p
E2.50 £1 80
90p
£1.14
90p
99p
74193 Eí35 E114
74196 E1 81 L1.34
LINEAR IC's
ES -00
70*
565
p in DIL
pin DIL
7098/14 pin DIL
35*
5668 pin DIL
El 50.
741 8/14 pin DIL
20*
5678
DIL
£2'00"
pin
38014 pin DiL
7488 pin DIL
90
384
381 14 pin DIL
1.60
5558 pin DIL
45
CA3016 14 pin DIL 50"
Matching charge 20p per pair. P L P 20p- Overseas 80p.
SEND SAE FOR COMPLETE LIST.
301A
8
35
55
pin DIL
307
309K
3900
99
HIGHAM MEAD,f CHESHAM,f BUCKS. Tel. (02405) 75154
VAT-Please add t% except items marked
C
I
'
£lß.95
Comp,etewdhthree
s
coloured lamo
100wan
that Bash in,lepe andom
25°%,
t ENGTH
14.41 inches
1J
for use
W,red ready
which are
TWIN BANKS LIGHT
(less lamps)
FL'ASNERUNI1
=
1,
Rttmg
412
f9.55
.1,
F.Eti.sngf10-35
Far.,
MASTER UNIT WATER
TYPE A SPOT
(less lamp)
CHANNEL
£30.95
[J
A*,
ót0p
wvulßuGSawp
,
0440
BC Fitting
TYPE B
UNIT
B.0
Sound to Light
3 BANK UNIT
9_
BC.
Fitting
E S
Fitting
£1.95.4* £2.12
nutmeg. Lens, Surnage. Manehestar
MIO INA. Telephone (061) 432 4915. Shop hours Dally 9-5.30 pm; 9-1pm Sate.
pg'
s*wJSn,
1 1L6
cs'n
I
UNIT
*it,: Length
Fitting
se....
3 lemon
gv.18
4
tiles
O.C. or
LPRICES ieCLdety.AT. pod
11/1[01
TWIN BANK12 LIGHT
p
100 WATT SPOT LAMPS
RED, YE L LOW. GRE EN
BLUE,
saco
CLEAR
16
15A
list value. If under,
3
NORTHERN BRANCH:
10A
TRIACS (PLASTIC TO -220 PKGE, ISOLATED TAB)
PRICE STABILIZATION POLICY
All commun/cations
15p
BA
rNry,T SOCKET
DISCOUNTS
13p
REO LED ONLY
GREEN CLEAR AMBER
175
andom
EL ECTRÖ A
2
1.75
IS the
U.m1si
PO
TuxteIII
.,
1
313/4
p Cx
Fitüng c1`ß68
ad 2
-
I
liesxs lamps)
Fitting
LU0
for illustrated helot S nee lis
ENGINEERING CO. LTD..
ALBEN
WORSTHORNE,
THE
DEPT. P W
CRESCENT
BURNLEY. LANCS. TeIBurnley20940
Practical Wireless, May 1976
SUPERSOUND 13 HI -FI MONO
AMPLIFIER A superb solid state audio ampli-
Brand new
omponents
throughout. 5 silicon transietore plus 2 power output
transistors in push -pull.
fier.
HARVERSONIC MAINS OPERATED SOLID
STATE STEREO FM TUNER
HARVERSONIC SUPERSOUND
IO -1- IO STEREO AMPLIFIER KIT
Full wave rectification.
Output
watts
approx.
into
13
8
ohms. Frequency response 12Hz 30KHz
3db. Fully integrated
pre -amplifier stage with
separate Volume. Base boost
and Treble cut controls. Suitable
for 8 -15 ohm speakers. Input for
ceramic or crystal cartridge. Sensitivity
approx. 40mV for full output. Supplied ready built and
tested, with knobs, escutcheon panel, input and output
plugs. Overall size 3" high x 6" wide x 75" deep. AC
200/260V. PRICE 615.00. P. & P. 85p.
DE
LUXE STEREO AMPLIFIER
A.C. mains
200 -240
n
vg
transform
-
U s
i
heavy duty
fully isolated
mains
er with full
wave recti-
fication
giving
adeq u a t e
smoothing with negligible hum.
Valve line up:- 2 x ECL86 Triode Pentode.. 1 x EZ80
as rectifier. Two dual potentiometers are provided for
bus and treble control, giving base and treble boost and
out. A dual volume control is used. Balance of the left and
right hand channel, can be adjusted by means of a sepa-
rate 'Balance' control fitted at the rear of the chusi..
Input sensitivity Is approximately 800m /v for full peak
output of 4 watts per channel (8 watts mono). Into 8 ohm
speakers. Full negative feedback in a carefully calculated
circuit, allows high volume levels to be used with negligible
distortion. Supplied complete with knobs, chassis size
11 "w x 4"d. Overall height including valve. 5 ". Ready
built & tested to a high standard.
512.50. P.&P. 95p.
ALL -PURPOSE POWER SUPPLY UNIT 200/240v. A.C.
Input. Four switched fully smoothed D.C. outputs giving
6v. and 75v. and 9v. and 12v. at 1 amp on load.
Fitted Insulated output terminale and pilot lamp Indicator.
Hammer finish metal case overall size 6" x 95" x 25 ".
Ready built and
PRICE E6.35 P, & P. 85p.
YYNAIR & RETINE SPEAKERS & CABINET FABRICS
app. 54 in. wide. Our guise 2160 yd. length. P. & P. 35p
per yd. (min. 1 yd.). S.A.E. for eamplee.
HARVERSON'S SUPER MONO AMPLIFIER
A super quality gram amplifier using double wound fully
Isolated mains transformer, notifier and ECL82 trlod
pentode valve as audio amplifier and power output
stage. Impedance 3 ohms. Output approx. 3'6 watts.
Volume and tone controls. Chassis size only 71n. wide
x Slm deep x gin. high overall. AC mains 200/240,.
Supplied absolutely Brand New completely wired and
tested with good quality output transformer.
P. & P. 86p
BARGAIN PRICE
£5.00
BRAND NEW MULTI -RATIO MAINS TRANSFORMERS. Giving 13 alternatives. Primary: 0-210 -240,.
Secondary combinations 0- 5- 10- 15- 20- 26- 30- 36- 40 -60v.
half wave at 1 amp. or 10 -0-10, 20 -0-20, 30- 0 -80v. at
2 amps full wave. Size 910. long x 311n. wide x 31n. deep.
Price 2800 P. & P. 75p.
MAINS TRANSFORMER. For power
Prl. 200/240v. Sec. 9-0 -9 at 600 mA.
Prl. 200/240v. Sec. 12 -0-12 at 1 amp.
Prl. 200/240v. Sec. 10 -0-10 at 2 amp.
supplies.
2160. P.
51.65. P.
22 85. P.
&
&
&
P. 86p.
P. 56p.
P. 70p,
GENERAL PURPOSE HIGH STABILITY
TRANSISTOR PRE -AMPLIFIER
For P.U. Tape, Mike, Guitar, etc. and suitable for
use with valve or transistor equipment. 9 -18v.
battery or from H.T. line 2001300v. Frequency
reeponee 15Hz- 25KHz. Gain 26dB. Solid encapsulation size 11" z 15" z 5 ". Brand new complete
with Instructione. Price 21110. P. & P. 15p.
QUALITY RECORD PLAYER
1k
141
o
f
All pilous and specifications correct
at lime of press and 'object to
alteration without polios.
Practical Wireless, May 1976
will suit any other standard etereo amplifier. The design
incorporates the very latest circuitry technique. with highgrain, low noise IF stages. Automatic frequency control to
lock -on" station and prevent drift. IC stereo decoder
for maximum stereo separation. L.E.D. for stereo beacon
indicator. Nominal output of tuner 100mV. Approximate
size 121" wide x 8" deep by 2I" high. Supplied ready
built, fully tested and fully guaranteed. A/C Mains
200/240V (not available in kit form).
SPECIAL OFFER for I month only 625 +
LI.20 p. & p.
LATEST ACOS OPO1 /180 mono compatible cartridge with
t/o stylus for LP /EP /78. Universal mounting bracket.
8175 P. & P. 18p.
CERAMIC STEREO CARTRIDGE. Universal Mounting
brackets and turnover stylus. 70mV per channel output.
ONLY 8806 + 18p P. and P.
SONOTONE (MARC COMPATIBLE STEREO CARTRIDGE
T/O stylus Diamond Stereo LP and Sapphire 78.
ONLY 5862 P.
P. 10p. Alm available fitted with twin
Diamond T/O stylus for Stereo LP. 4618, P. A P. 18p.
CRYSTAL
LATEST
T/O
STEREO / COMPATIBLE
CARTRIDGE for EP /LP /Stereo /78. SIPS P. a P. 18p.
LATEST T/O MONO COMPATIBLE CARTRIDGE for
playing EP /LP /78 mono or stereo records on mono
equipment. Only 5176, P. & P. 18p.
LATEST HIGH SENSITIVITY UNI- DIRECTIONAL
SLIMLINE CONDENSER MICROPHONE as used by
professionals. Very low acoustic feedback. 600 ohms
impedance. Only 61400 + 50p P. & P.
t
translators including 531con Translators in the tint five
stages on each channel resulting in even lower noise,
level with Improved sensitivity. Integrated pre -amp with
Baas, Treble and two Volume Controle. Suitable for use
with Ceramic or Crystal cartridges. Very simple to
modify to suit magnetic cartridge -instructions included.
Output stage for any epeakere from 8 to 15 ohms. Compact
design, all parts supplied including drilled metalwork
high quality ready drilled printed circuit board with
component Identification clearly marked, smart bitched
anodised aluminium front panel with matching knobs,
wire, solder, nuts, boite-no extras to buy. Simple step
by step Instruction enable any constructor to build an
amplifier to be proud of. Brief specification; Power
output: 14 watts r.m.s. per channel into 6 ohms. Frequency response ±3dB 12- 30,000 Hz Sensitivity:
better than 0OmV Into 1Mp. Full power bandwidth:
±8dB 12- 15,000 Hz. Bane -boost approx. to ±12dB.
Treble out approx. to -16dB. Negative feedback 18dB
over main amp. Power requirements 30v. at LO amp.
Overall Size 12 "w. x 8"d. x 25 "h.
Fully detailed 7 page conetructlon manual and parte
list free with kit or send 25p plus large S.A.E.
AMPLIFIER KIT
81800 P. d P. 65p
(Magnetic Input components 33p extra)
POWER PACK KIT ..
..
2685 P. d P. 85p
..
..
..
CABINET
6665 P. & P. 769
SPECIAL OFFER-only L24 if all 3 items
ordered at one time including p, & p.
Full after sales service
Also available ready built and tested 88850. P. & P. 41.
Note: The above amplifier Le meltable for feeding two mono
source, into inputs (e.g. mike, radio, twin record decks, ,le.
and wilt then provide mixing and fading fatilitle, for mad
Pye VHF/FM Tuner Head
covering 88 -108 M /Hz. 10.7
M /Hz I.F. output 7 -8 Volt +
earth. Supplied pre- aligned ,
with gang full circuit diagram
and connection details supplied. Beautifully made with
precision-geared FM and 929
Pf + 328Pf A.M. Tuning
Gauge only 2350 + P. & P.
'
dim powered
Mullard LP1159 R.F. -I.F. Double Tuned Amplifier
Module for nominal 470 KHz. Size approx. 24" x 15" x
5" 7.6 Volt + earth. Brand new pre -aligned. Full epeci
Ocation and connection details supplied. 6860. P. & P. 12p
r!
y
,....+
HiFi
w
I
Discotheque
t
u,, etc.
S -VALVE
(1=11
-
#00Y 4)wr0.1
1
I1
AUDIO
AMPLIFIER HA04 MK II
tion ofd for HI -F1
lion of records. A.C.
C. Mains
operation. Ready built on
plated heavy gauge metal
chassis, elm 75 "w. x 4'd. x
{f
h.
Incorporates
ECM,
PRECISION MADE
EL84, EZ80 valves. Heavy
duty, double wound mains
transformer and output transformer matched for 3 ohm
speaker. Separate volume control and now with improved
wide range tone controls giving bass and treble lift and
cut. Negative feedback line. Output 45 watts. Front
panel can be detached and leads extended for remote
mounting of controls. Complete with knobs, valves, sto.,
wired and tested for only 2875. P. & P. 85p.
Push Button Switch bank. 8 Buttons giving 16 S/P C/O
interlocked switches plus 1 Cancel Button Plus 3 d/p c /o.
Overall size 5" x 24" x 1 ". Supplied complete with
chrome finished switch buttons. 8 for 6160 + 10p P & P.
HSL "FOUR" AMPLIFIER HIT. Similar In appearance
to HA84 above but employs entirely different and
advanced circuitry. Complete set of parts, eta 47.75
P. d P. 86p.
35p.
g.
Iu ne
HI -FI LOUDSPEAKER SYSTEM MK I I
Beautifully made, simulated teak finish enclosure
with atttactive slatted front. Size 185" high x 105"
wide x 9" deep (approx.). Fitted with E.M.I.
Ceramic Magnet 13" x 8" bus unit, H.F. tweeter
unit and crouover. AVAILABLE IN NOMINAL
Ohm, 8 Ohm or 18 Ohm impedance (state which).
£12.50 each Carr. 21.60.
Cabinet Available Separately 4750, Carr. 21.20.
Also available In 8 ohms with EMI 13" x 8" bus
speaker with parultic tweeter 21100, Carr. 21'00.
LOUDSPEAKER BARGAINS
bin. 8 ohm 41.46, P. & P. 35p. 7 x 41n. 8 ohm 21SO, P. & P
48p. 10 x Sin. 8 or 15 ohm 4/'50, P. is P. 75p. E.M.I
8 e 61n. 8 ohm with high flux magnet 4806, P. d P. 50p
E.M.I. tweeter. Approx. 85 ". Available 3 or 8 or 15 ohms
62 00 + 26p, P. & P.
I
A really first-class Hi -Fi Stereo Amplifier Kit. Uses 14
SPECIAL OFFERS
OUR PRICE
AMPLIFIER MK. U
A top quality record player amplifier employing heavy
duty double wound mains transformer, ECC88, EL84,
and rectifier. Separate Bau, Treble and Volume controls.
Complete with output transformer matched for 3 ohm
speaker. Size 71n. wide is 31n. deep o Sin. high. Ready
built and tested. PRICE 4660, P. & P. 90p.
ALSO AVAILABLE mounted on board with output
transformer and speaker. PRICE 6776, P. & P. 21.
Open 130-5.30 Monday to
Friday. 0.30 -S Saturday
Closed Wednwsday.
low introductory price!
Designed and styled to match our 10 + 10 amplifier but
4
TEREO -DECODER
SIZE 2" x 3" x 5" ready built. Pre aligned and tested. Sens. 20 -560 mV
or 9 -16V neg. earth operation. Can
be fitted to almost any FM VHF radio
r tuner. Stereo beacon light can be
fitted If required. Full details and
netructions (inclusive of hints and
bps) supplied. 2625 plus 20p. P. & P.
Stereo beacon light if required 45p
xtra.
Enjoy fabulous stereo radio at this
"POLY
PLANAR" WATER -TYPE, WIDE RANGE
ELECTRO- DYNAMIC SPEAKER
Elise llf" x 1455" x 1,j" deep. Weight 190e, Power
handling 20W rms. (40W peak). Impedance 8 ohm only.
Response 4OHs-20kHz. Can be mounted on ceilings,
walls, doors, under tables, etc., and used with or without
baffle. Bend S.A.E. for full detalle. Only 57 68 each.
P. & P. 70p.
Now also available 8 ".
8 ohm 10 watts, rms. 20
watt peak 40 Hz- 20,000 Hz. Overall depth 1 ". Ideal for
HI -FI or for use in care 6615 + 40p p. & p.
-
10/14 WATT HI -FI
AMPLIFIER KIT
A stylishly finished
monaural amplifier
with an output of
14 watts from 2
EL84s in push -pull.
Super reproduction
of both music and
speech, with negligible hum. Separate
Inputs for mike and
gram allow records
and announcements
to follow each other.
Fully shrouded section wound output transformer to
match 3 -16 speaker and 2 Independent volume controls,
and separate bue and treble controls are provided
giving good lift and cut. Valve line -up 2 EL84s, ECCE,
EPOS and EZBO rectifier. Simple Instruction booklet
25p + SAE (Free with parte)' AU puts sold sePasately.
ONLY 412 50 P. & P. 21'25. Also available ready built
and tested 21687 P. & P. 61'20.
Limited number of the latest Wilt
Auto /Manual changer de-luxe. Lightweight
SPECIAL OFFER
C141RI
tubular arm, cue -ing lever bias compensator 41400 +
2110 p. & p.
Prices include VAT at Current Rate
HARVERSON SURPLUS CO. LTD.
(Dept. P.W.) 170 HIGH ST., MERTON, LONDON, S.W.19 Tel.: 01 -540 3985
A few minute, from South Wimbledon Tube Station.
SEND STAMPED ADDRESSED ENVELOPE WITH ALL ENQUIRIES
(Please write clearly)
PLEASE NOTE: P. it P. CHARGES
QUOTED APPLY TO U.H. ONLY.
P. & P. ON OVERSEAS ORDERS
CHARGED EXTRA.
17
print -a -kit
F
Sere
ê
o-
now bring you
PAK STRIP
(Pat. applied for)
rß'
The easiest way yet to mount D.I.L.
IC's etc.
PAK STRIP is a thin, flexible fibre
glass board with a self- adhesive
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You can bend it, drill it, cut it with
scissors prick holes in it, solder to it,
stick it to anything.
It is so versatle its many applications
are limited only by the Ingenuity of the
user.
.41
Star points of PAK STRIP
MYSELF"
9 MADE IT
feel ! Imagine how impressed \
* Will cut with scissors
* Has self- adhesive backing
be used to surface solder
* Can
D.I.L. IC's, light displays, etc.
Imagine the thrill you'll
people will be when they're hearing a programme on a
modern radio you made yourself.
Now! Learn the secrets of radio
and electronics by building your
own modern transistor radio!
Practical lessons teach you sooner
than you would dream possible.
a wonderful way to learn -and pave the way to a
new,
What
better -paid career! No dreary ploughing through page after
Technatron
page of dull facts and figures, With this fascinating
Course, you learn by builditlg!
a
*
*
etc.
* bolts
No need to drill holes for nuts and
... just stick down ...
REMEMBER! a surface soldered D.I.L.
IC will remove easily.
learn faster than you
ever dreamed possible.
Yes! Faster than you can imagine,
you pick up the technical know how
you need. Specially prepared stepby -step lessons show you how to:
read circuits -assemble components
-build things -experiment. You
enjoy every minute of it!
You get everything you need.
Tools. Components. Even a versatile
Multimeter that we teach you how
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AT NO EXTRA CHARGE! And
this is a course anyone can afford.
(You can even pay for it by easy
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No matter how little you know now.
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You become somebody who makes
things, not just another of the
millions, who don't understand. And
you could pave the way to a great
new career, to add to the thrill and
pride you receive when you look at
what you have achieved. Within
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because our famous courses go
right up to City & Guilds levels.
Send now for FREE
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44
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Find out more now! This is the
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To: ALDERMASTON COLLEGE
DEPT. CPW 17, READING RG7 4PF
-
CPWI7
Also at our London Advisory Office, 4 Fore Street
Avenue, Moorgate, London, EC2Y 5EJ Tel: 01.628 2721
Yes. I'd like to know more about your course. Please send
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a go
011OD
L_
Type B
General purpose
group board
11 8-pin D.I.L. IC's
35p plus a SAE VAT incl.
Sample PAK STRIP
11.80 VAT 1. Postage inc.
8" x 5" board with 6 strips
L3 00 VAT A Postage inc.
8" x 10" board with 12 strips
Please state Type A or B when ordering: S.A.E for details.
invoice:
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Order
TERMS: Cash
quantity prices invited. Overseas add 25p per sheet.
>x
rgrä°cekg°
406
Sharrowvale Road, Sheffield SII UP ENGLAND
So fast, so easy,
this personalised course
will teach you even if
you don't know a thing
Name
HOME OF
CID 'OD
One Type A PACK STRIP will mount
Electronic Supplies,
You build a modern Transistor
Burglar Alarm. You
Radio
. a
learn Radio and Electronics by doing
actual projects you enjoy- making
things with your own hands that
you'll be proud to own! No wonder
it's so fast and easy to learn this way.
Because learning becomes a hobby!
And, what a profitable hobby.
Because opportunities in the field of
Radio and Electronics are growing
faster than they can find people to
fill the jobs!
No soldering -yet you
Miniature and standard potentiometers can be mounted on the
take-off pads
Type 8 can be used for grouping
cables, mounting diodes, resistors
BIET
BRITISH INSTITUTE OF ENGINEERING TECHNOLOGY
SOUTHERN VALVE COMPANY
P.O. Box
144,
BARNET, Herts.
Telephone: 01- 440 8641. Mail order only. Most leading makes.
ALL NEW á BOXED VALVES
AZ31
DY86 /7
DY802
EB91
ECC81
ECC82
ECC83
ECC85
ECC88
ECH42
ECH81
ECH83
ECH84
ECL80
ECI.02
ECL83
ECL86
EF80
EF85
EF86
EF89
37p
440
P1.82
PC97
PC900
44p
OY501
0530
70p
PCC84
40p
PCC85
48p
90g
57p
57p
51p
76p
PCC88
69p
550
P0089
F00109
38g
46D
PCF80
PCF82
PCF86
88p
PCF200
44p
559
649
61' 05
41p
57p
PCF801
55p
PCF802
PCF805
00g
35D
68p
90p
38g
489
489
32g
40g
40p
F.YBfi /7
701,
EZ81
54g
44p
62p
60p
41p
E5í94
EY61
PC86
PC88
37D
E1190
EL84
PD500
PFL200
PL36
EZ40/1
EZ80
EF183
EF104
EL34
EL84
EL84
59e
38p
33p
90p
49p
72p
40p
46p
210
89p
41p
PCF806
PCF808
PCH200
6186
50p
6125
86p
PCIA2
41D
PCL84
PCL85
52g
08g
68p
PCL806
FOL86
SaD
PCL'200
6180
PCL85
530
PIA1
PL81A
PL83
PL84
PL500
PL504
PL508
pL509
PL519
PL802
Py33
PY81/3
DY88
Py800
PY801
PY500
l
PYSOOA f
6850
81p
671'
55p
80p
42p
51p
alp
85g
881,
6110
6800
6810
12 25
57p
43p
45p
45p
45g
6110
UBF89
44D
UCC85
51p
80p
48p
46p
64p
75p
460
1,01142
UClíBl
UCL82
UCL83
UF41
UF89
UL41
SOp
UL84
ÚY85
U25
U26
48p
57g
80g
76p
11191
80p
6/30L2
6BW7
80p
6F23
6F28
6V6
20L1
251'4
3001
30015
30017
30(118
30F5
30FL1
30FL2
30LI
30L15
30L17
30P12
301'19
30PL1
30PL13
30PL14
30PL15
30P4MR
75p
80p
76p
52D
75p
900
44p
86p
88p
11.35
88p
6108
6108
44p
880
610
80p
11.00
6160
870
6180
6190
99y
We offer return of post service. Post free over £1000.
Most other types available.
Items in stock at time of going to press but subject to possible
market fluctuations if unavoidable.
TRADE. Representative will call West Country á S. Wales,
also Suffolk, Norfolk, Hunts, etc.
DISCOUNT PRICES, CWO only.
Enquiries sa.e.
One valve post 7p, each extra valve 6p (maximum 50p) LISTS
s.a.e. please.
Practical Wireless, May 1976
Sni products
FROM BI-PRE-PAK
Stîriit
THANKS TO DEMAND AND STEPPED-UP PRODUCTION
THIS HIGH -FIDELITY POWER AMPLIFIER MODULE
SS.125 `9óßs £6.50
INCLUDING POSTAGE AND V.A.T.
Not only is this Stirling Sound's
best audio amplifier yet; it rightfully qualifies as one of the best of
its kind yet made available to
constructors. Intended above ali
for high -fidelity, the characteristics
of the SS.125 are such that it can
be used in many other applications
where dependability is the prime
consideration. The SS.125 integrates
well with other S.S. units as well
as those of other manufacturers.
Incorporates new circuitry using
pair
a complementary long- tailed
input and full complementary
output circuits to give lab standards
of performance.
into 8 n using 50V
22 watts R.M.S. into 4 D using 33V
(Low imp. not less thon 4 U )
OUTPUT
25 watts R.M.S.
* DISTORTION *
Less than
FREQUENCY
RESPONSE
HIGH
Z
INPUT
INPUT
SENSITIVITY
0.05% at all power levels
(From 10Hz to 10KHz)
7-
IdB
IdB
15
10
Hz to 30 KHz (4 n)
Hz to 30 HKz (8 n)
S5.125
100Kohms(40dBgain /100x)
150mV
Power Amp.
£5.20
for 25W. R.M.S. out
Post paid U.K.
+ £1.30 VAT
(Inc. built on heat sink type
mounting bracket) 41" x 3" x
SIZE
>r"
.. And
More Stirling Sound Modules
Tuner Iront end. Ganged, geared variable tuning,
88- 108MHz. A.F.C. facility
SS.202
I.F. amp. A metre and /or A.F.C. can be connected
(size 3 "x2 ")
POWER SUPPLY
Robustly designed units
in each of which Is a
stabilised take -off point
to provide for tuner,
pre -amp and control
stages.
SS 2,2
£2.65
Stereo decoder for use with SS.201 and 202 or any
good F.M. tuner. A LED beacon may be attached
(3" x 2 ")
SS.203
E5.00
£3-6a
SS.312
SS. 318
SS. 324
SS.203
watt amplifier to run from 12V. (34" e 2"
} ")
5
SS.110
Similar to SS.105 but more powerful giving 10W. into
e
4ohms
watt module when used with 34 volts into
£3.00
20
Delivers 40 watts R.M.S. into 4 ohms using a 45V/2A
supply such as our SS.345 the power and quality
of this unit are superb-Size 4 "x3 "x} ".
£3.75
SS.100
Active tone control stereo. i15df3 lift-cut bass /treble
£1 60
SS.102
Pre -amp for ceramic
£1.60
SS.t03
Active pre -amp (stereo) Inc. R.I.A.A. and line feed
back
4
SS.
L2.25
105
KIT
VAT at
25% must be added to total value of order except for items marked
or (0%) when VAT Is to be added at 8 %. No VAT on overseas orders. POST
& PACKING add 30v for UK orders unless marked otherwise. Minimum mail
order acceptable -£1 Overseas orders, add LI for postage. Any difference
will be credited or charged. PRICES subject to alteration without notice.
AVAILABILITY All items available at time of going to press when every
effort is made to ensure correctness of information.
27.95
BUILT
&
TESTED
f
£10.50
81- PRE-PAK LTD
Co Reg No 820919
222 224 WEST ROAD. WESTCLIFF ON-SEA. ESSEX SSO 90F.
TELEPHONE: SOUTHEND (0702) 46344
'
Send us a large S.A.E. with 10p stamp and we will send you the latest
Bi- Pre-Pak catalogue free by return. Packed with useful lines, its a
f,11 , o v saver
Itl
E
- - - -- E
ltttttt
ITO STIRLING SOUND (BI- PRE -PAK LTO) 220,222 WEST ROAD.
WESTCLIFF-ON-SEA, ESSEX SSO DDF
Please send
for which
Order your Stirling Sound products from
CHEQUES /MONEY ORDERS PAYABLE TO BI- PRE-PAK LTD
£460
A USEFUL CATALOGUE -FREE
SS 140
TERM S OF BUSINESS:
Practical Wireless, May 1976
34V/2A
£S 20
45V/4A
£0.25
(all above are at 8% V.A.T.)
£4.15
Even better than the original B -P -P version, thousands of which are
in use saving motorists appreciable time and money for petrol. Very
easy to Install. The Stirling Sound model incorporates switch for
instant change to conventional ignition; immediate adaption to pos.
or neg. earth return; anti- burglar immobilising switch, pre -set control
for rev. limitation. There are no exposed parts, the unit, on p.c.b.
being housed in strong enclosed metal box.W ith instructiors and leads.
Size 7f" x4} "x 2} "ex. switches.
£2.75
SS.120
SS.334
SS. 345
£3`75
new Stirling Sound Capacity Discharge
Ignition Unit for your car the "Super Spark" Mk.5.
£2.25
SS.140
12V/1A
18V /1A
24V/1A
A
AUDIO MODULES
SS.105
5 NEW
Stirling Sounds
All designed specially for low- budget needs with
easy to follow instructions
F.M. TUNER UNITS
SS.201
high
ne.
I
enclose £
V.A.T.
i..
I
NAME
ADDRESS
rI
I
PW5B
was
gum
19
ESSENTIAL BOOKS FOR RADIO AMATEURS
AMATEUR RADIO TECHNIQUES
Edition
1976
RSGB AMATEUR RADIO
CALL BOOK
Incorporates all new callsigns and amendments notified
between August 1974 and August 1975.
Also includes valuable operating data such as band plans,
beacons, prefix list, ITU zone list, beam headings and QSL
Bureau sub-managers, and lists of clubs and groups.
Price £1.47 post paid
168 pages
(5th edition)
by Pat Hawker, G3VA
Basically an ideas and source book, this ever -popular work
brings together a large selection of new circuits and devices
and many constructional and fault -finding hints.
In this latest edition some 50 pages of new material have
been included and other sections have been revised and
expanded.
304
Price £2.52 inc. p. & p.
pages
Over
diagrams
700
RSGB LOG BOOKS
TRANSMITTING: Standard,
RADIO DATA REFERENCE BOOK
by G. R. Jessop, CEng, MIERE, G6JP
An invaluable source of essential radio data conveniently
gathered into one hard -bound volume measuring 51in by 9in.
Price £1 32 post paid
150 pages
96p; de luxe, £2.44; minilog
(for mobile and portable), 80p. All post paid.
RECEIVING: £1.20, post paid.
The Receiving Log Book, similar in format to the transmitting log books, is designed specially for the short -wave
listener who wishes to make a proper record of amateur
stations heard.
These are just a few of a complete range of technical publications, log books and maps for the radio
amateur. Send a large stamped self- addressed envelope for the complete list.
The RSGB is the national society representing all UK radio amateurs. Membership is open
to all interested in the hobby: write to the membership section and ask for full details.
RADIO SOCIETY OF GREAT BRITAIN
DOUGHTY STREET,
35
Ins. LI
E63-70
E97-50
L63-00
Sansul AU2200
AU4400
Pioneer SA5300
RECORD DECKS
P &P 85p
Ins. 50p
Garrard SP25 Mk. IV
Garrard SP25 Mk. IV,G800
Plinth & Cover
BSR MP60
Connoisseur BD1 Kit
BD2 Chassis /SAU2
SAU2 Pick -up Arm
SCU1 Cartridge
Pioneer POND
Plinth -cover for Garrard or
BSR
SPEAKERS P &P 45p
EMI 13" x 8 ", 3, 8 ohm plain
13" x 8" Bass unit, 15 watt
61" 8 ohm, 10 watt
8
"8 ohm,
10
watt
watt
x 5" C. Meg. 5
or 15 ohm
8" x 5" Dualcone 0 ohm,
10 watt
Elac 61" 8 ohm Dualcone
8 8 ohm Dualcone
Baker Group 2512", 8 or 15 ohm
Adastra 10" 10 watt, 15 ohm
Goodmans 8" x 5" 8 ohm
Global 8 ohm 5 watt (pair)
Richard Allan 12" 60 watt
8 or 15 ohm
Richard Allen 12" Dualcone
8"
-837 8688
High Quality
Construction
Kits. stocked
at all branches
Send for
all items subject to manufacturers
increase and availability
,Í
V.A.T.
P &P 95p
01
PERSONAL CALLERS
ARE WELCOME!
ALL PRICES
INCLUDE
AMPLIFIERS
LONDON, WC1N 2AE TEL:
L2390
L361S
£11
00
L16-56
E42-61
£17.91
L7-43
LW 25
£5.31
£3.75
L7.25
£4.09
E5.93
3. 8
£2.02
£4.12
E3.06
L3.37
LI500
E4-61
£2.12
E9-93
E12-9S
£13.05
WHARFEDALE
SPEAKER BARGAINS
P &P 85p
Ins. 50P
C31-87
Chevin (pair)
£40 00
£59S0
E26.1/
Denton 2 (pair)
Linton 3 (pair)
Linton 2 (kits)
KIT FORM CABINETS
Ins. 50p
12 "x8 "x4} "(8x 5 or 704 cutout) E3 34
12 "x12 "x71" (10 ",8x5.8", 61"
E475
and 31 ")
18 "x11 "x71 "(8 "x31" or13 08) E5.94
22 "x14"x71 "(12 "x31" or 13x8) LT 18
TWEETERS & CROSSOVERS
Teak Veneer
P &P 85p
SC5M stet. coram.
Sonotone
9TAHC or 9TAHC G
(Dlam)
3509 stet. ceram.
Audio Tecnica AT55
Empire 999 REX
Goldring 6850
6800
E2 75
LI
£1.20
L2.2S L1-20
E2 2S
E2.25
EC IS
-
Type
noise
C60
C90
C120
37p
4$p
S9p
£3-SO £1.75
L5.25 EI-75
LS-2S L1-75
L9-OS L3-S0
Styli
M55E
M75ED Type 2
M75EJ Type 2
LS-10 E4á3
L7-$1 LO. 10
£14.06 E10.31
E12.1S
CARTRIDGES
S.
STYLII
Cart.
P &P 25p
Acos GP91i2SC or
3SC (ater. comp)
G P93í1 or 95,/1
ster. cryst
GP9411 or 96/1
star. ceram.
GP101 cryst. comp.
GP104 ster. ceram.
BSR X5M or H5X
tryst. comp.
SX6M or SX6H
tryst. stet.
D.D.
Styli{
E1.60 £1 20
£1.60 £1.20
-
L2-00 £1.20
E1 00
£2-IS £1.20
LI
65
Et
20
L2-25 E1-20
MICROPHONES
P
5"
51"
S9p
7"
92p
70p
&P 25p
L2-I2
crystal
DM180 Dynamic omnl -dir. ball
metal
E6.11
UD13050K 600 ohm, uni -dir, ball
metal
E7.31
CONDENSER MIKE 600 ohm,
L10-62
uní -dir.
Cassette STICK MIKE with R
Control on/off switch (2-S &
3.5 mm) J /Ply)
Cassette STICK MIKE with Rf
Control (Philips Type)
LI-56
LI.97
BATTERY ELIMINATORS
P &P 25p
240v input 6, 7.5 or 9 volt output
12v d.c. Input (specify output
6. 7.5 or 9 d.c.) at 300rnA
ex
SOP
l}p
CI-IS
£1-67
IIp
E116
EO13
£0.40
E2.32
£1.99
P &P 25p
Sind.
CM70 Planet stick metal, switch
Memor-
Philips
CASSETTE CASES
Cassette Head Cleaner
BIB Stereo Test Cassette
AMPEX Head Cleaner Demag
TAPES
L7.61
P &P 25p
Cone Tweeter 8 or 15 ohm,
E3-68
10 watt
Et93
Cone Tweeter 8 ohm, 3 watt
£i 72
Horn Tweeter 8 ohm, 20 watt
Dome Tweeter 8 ohm, 30 watt Lí-11í
Crossovers CN23 (3 ohm) CN28
E1.7S
(8 ohm), CN126 (16 ohm)
P &P 25p
Low
G800E
&
CASSETTES
28
G80014
Shure Carts
M446
catalogue!
LP
70p
02p
DP
Cases
32p
LI-IO LI
LI
-OS
Up
43p
99
SINCLAIR PROJECT 10
P
Stereo Pre-amp
Active Filter Unit
Z40 15 watt Amp.
Z60 25 watt Amp.
P25 Power Supply for 240
P26 Power Supply for 240
P28 Power Supply for 26)
FM Tuner
Stereo Decoder
016 Speaker
IC20 stereo amp. kit
PZ20 Power kit
-
&P 25p
E10-18
L9-9S
L7-1$
E9.06
-1.61
L10-56
C10.31
L111.18
£10.56
L9-31
E9-37
L6-S6
Send 25p for complete catalogue.
L2.75
ECU
PLEASE BRING THIS ADVERTISEMENT TO OBTAIN THE BENEFIT
OF THESE SPECIAL PRICES
i
EWMAR
NELECTRONICS
20
Mail Order Dept
PW4
Belmont St, Monton,
Eccles, Manchester.
Tel:061-789 5268
Manchester
30 -32 Shudehill. tel
i
061.832 7710
Leeds
4
New Market St tel 0532 42708
Liverpool
15
Whitechapel tel 051.236 0738
Practical Wireless, May 1976
These days you can Dial -a -Van, Dial -a- Recipe, Dial -aPop Tune, even Dial -a -Wine. But Home Radio Components Ltd. have been offering such a service for years!
Those of you who already own one of the renowned
Home Radio Components catalogues already know all
about it. For the benefit of those who are still struggling
along without one, here is how you set about it.
1.
Purchase a Home Radiio
(See details further on).
2.
Join the HRC Deposit Account scheme, by simply
signing the form enclosed in the catalogue.
telephone number, which after business
connected direct to an answerphone.
3.
Send it to HRC with your deposit. The deposit is half
of whatever credit you require; i.e. if you want £10.00
you send £5.00.
4.
You will receive back: a copy of your Agreement,
special Order Forms, pre -paid envelopes for sending
them, a Record Card on which to note your spending,
and simple instructions to enable you to use the
service to best advantage.
Like the idea? Then send for your Home Radio Catalogue
straight away. It costs only 54p plus 45p postage and
packing, and it contains 6 vouchers each North 5p when
used as directed, so you can soon get back 30p of your
investment. Moreover, if you join the Deposit Account
scheme you will receive a new catalogue free whenever
it is reprinted. ft's hardly surprising that o'rer a thousand
customers are already using this simple method of buying
their components. Try it now you'll never regret it. Send
99 pence by cheque, Postal Order or Giro with the coupon
below, and soon you'll be twirling your telephone dial
whenever you urgently want some parts!
Components Catalogue.
Now you are all set to dial your component orders any
hour of the day, any day of the year -including Sundays,
holidays, even Christmas day. You have your own exclusive
hours
is
Today's finest Components
The price of 99p applies
only to customers in the
U.K. and to BFPO Addresses.
54 p plus 45p
PACKyátalO.7Ve
POST &
7
Please write your Name and Address in block capitals
I
NAME
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ADDRESS
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HOME
234 -240
L
RADIO (Components) LTD. Dept. PW,
London Road, Mitcham, Surrey CR4 3HD
HOME RADIO (Components) LTD Dept. PW,
Practical Wireless, May 1976
(Regn. No.
London
I
234.240 London
Road, Mitcham,CR4 3HD
Phone
01 -648
8422
11
&itkí -
~
r
Designed by
TEXAS
SOLE U.K. DISTRIBUTORS - HENRY'S
Build the Tex,an Stereo amplifier, then you can be doubly proud! For a start,
you'll own a superb home entertainment
unit. And have had all the pleasure of
* Can be built Stage by stage
doing it yourself, with the Henry's kit.
Ask for leaflet 20.
E verything necessary
Look at the Texan specification
supplied
Fun afterssales service
Y
and guarantees.
Incorporating fully integrated stereo preamp
KIT PRICE
THE NATURAL FOLLOW-ON
KIT PRICE
£25.95
fne. VAT
Built and tested
E45.00 nc. VAT
+ E1.00 pbp.
£35.00
Inc VAT El obit
1
-THE
i
TEXAN FM TUNER KIT!
Build the matching Texan stereo tuner !Features
advanced vancap tuning. Phase lock loop decoder
Professionally designed circuit. Everything you need lis
in the kit. From the glass fibre pcb to the cabinet itself.
Excellent spec 2.5 uV aerial sensitivity. 500 my output
(adjustable). Tuning range 87 -102 MHz. Mains
powered.
The following items are in S/Hand cond.
MOD & H.T. Invertor unit about 15w mod H.T.
200/400v at 15OMa 12v I/P with cire £4.80. Tx
SUB ASS for 70/8OMc/s less valves with cire
about 20w £2.40. METER T.S. in case 9 x 7 x 5"
with 1Ma FSD meter, swts, etc £350. VIDICON
TUBES standard 1" types P849D & P842 tested
£960. FLOURESCENT CHOKES 5ft 65w £1 60
& 8ft 125w £2.20. HEAVY DUTY VARIACS for
240v 50c/s rated 20/25 amps with 200/250v driving
motor with limit swts £40. SCOPES MARCONI
type CT90 mains operation high speed pulse
Built and testeo E30.95 inc. VAT +509 pbp.
SPORT
VIDEO
all
excitement
the electronic
you could wish fort
An up- to- the -minute game. Plugs
into your own TV aerial socket
Switch on.And you're away
Choose your game- football, tennis
!
,
hole-in -the-wall Absolutely
sale. For you. Yourchildren.And
or
your TV. Mains powered.
List Price E42.50
inc. VAT +
C-INY.29.50
WHATEVER YOU DO, DON'T FORGET
YOUR LATEST
HENRY'S CATALOGUE!For this new edition, we have made
hundreds of changes and additions.
It has over 200 pages, containing
virtually everything for amateurs and
professionals. And you'll have no
bother at all finding everything you
want, because there's a complete
alphabetical index as well as a section
index. Together, they put you right on
course for the items you need. From
Sinclair projects to educational kits.
Oscilloscopes to panel meters. Coils ro
r. apacitors. Transistors to valves.
Loudspeakers to microphones - all at
repetitive prices. Over 200
pages of vital statistics- just for
ONLY
you! So send now tor your cop'
50p
209 cam pack
NaNRÿs
Over 5000
items inside,
Every copy
a
free
ee
50P voucher,
n,
LOWER SALES FLOOR,
taw
sT
22
scopes triggered high speed T.B. with int time
cal & Y shift voltmeter (note not suitable for
general purpose use) supplied with copy of
H /Book in transit case £26. OPTICAL MIRRORS
14f" dia. 11" deep at centre with centre hole 3f"
dia precision unit £15. TAPE DECKS BSR type
TD10 with two chan amps & P.U. £8.50 & TD2
with amps only £5-50. these two items callers only.
flew
Over 200
Pages.
Above prices inc carr/postage & V.A.T. Above goods
are new unless stated S/Hand. S.A.E. for list or enquiry,
shop open Tues to Sat.
FREE to Educational Establishments when
ordered on official headed notepaper.
CENTRES
SEEF. GWACE
404 and
Bantams
galore - Can0A0, LONDON W2
earaelit,
° ° °°
404,6 EDGWARE ROAD, LONDON W201-402 8381
1618LANVS
sheets £1.50. AERIAL TUNING coil ass Rx type,
A as 8 coils & trimmers covering long to s.w. in
scr box £1.70 type B as 6 coils & trimmers covering
s.w. £1.20. POLAR RELAYS precion type as two
coils of 3.5K octal base £150. YAXLEY SWTS
larger type inst swts 8p 12w 8b & 2p 23w 2b £1 40ea.
7p 23w 7b £1'70 & 6p 12w 6b £1.20. T.V. AERIAL
FILTERS made to fit in Ae lead fully scr box 4 x 1f x
11" fitted standard coax plug & sk. 4 for £1.20.
SPEAKER UNITS small horn spk for use on
M /Cycle 3 ohm with fix brk & cable spk 5 x 3" £2.50.
DIODES 300PIV 5 amps on H/Sink stud mt type
4 for £1. CRYSTALS FT243 type in range 5.6 to
8'6Mc /s 25Kc spacing 5 different for £1.40 also
Hc18 type min wire ended in range 13 to 19Mc /s
ex equip 10 for £1.50. TAG STRIPS solder type
24 way 10 for 70p.
:
50P P&P
'
5
1
Featured by PRACTICAL WIRELESS
low-field low -lime mains°transforerr; all
facilities and controls. Slim design, chassis
tare 6" it 2" overall. 20 watts per channel
RMS, less than 0.1l4 distortion at kHz.
also min type 3/10pf 10mm dia
1
\ \w.
and power amp, with a IC's, to transistors;
6 rectifiers and tener diodes. Plus stabilised
fib
10 for 80p.
for 50p. FEED THROUGH CONDS 1000pf/500v solder in type
10 for 50p. ERIE feedthrough filtercons 1750pf 250v
solder in type high grade filters 10 for £1. B.F.O.
UNIT '6Mc /s var freq with valve £2. MINIATURE
COILS with scr cans & slugs 5mm dia formers
10 for 50p. REMOTE Tx/Rx crystal selector provision
for 6 Rx & 6 Tx crystals Hc6/u type also 6x BC108 &
6x trimmers £1.60. I.F. TRANS min type 455/465Kc
transistor type 3 for 65p. TAPE HEADS 8 track for 1"
tape low imp £1.20. MIN ROTARY SWT2p 5w; x1"
shaft 2 for 60p. CRYSTAL FILTERS all 10.7Mc /s min
type 3OKc b.w. £1.30. 15 & 12Kc b.w. £1.60. INTEGRATED CIRCS three types CA3014 I.F. amp & disc.
ULN -2111A wide band amp with product det. TAA300
watt into 8 ohm one of each with data
audio amp
TRIMMERS air spaced ceramic 20pf
231.TOTTENHAM CT. RD.,
LONDON W1 01 -636 6681
94/96 UPPER PARLIAMENT STREET, NOTTINGHAM. 0602 -40403
ALL MAIL TO HENRY'S RADIO, 303 EDGWARE ROAD, LONDON
A. H. SUPPLIES
122
HANDSWORTH ROAD
SHEFFIELD, S9 4AE
Phone 444278 (0742)
W2
Practical Wireless, May 1976
Completely Solderless Electronic
Construction Kit. Build these projects without
soldering iron or solder
* 4 Transistor Earpiece * 7 Transistor Loud* Batteryless Crystal
Radio
speaker Radio
Radio
* Signal Tracer
MW/LW
* One Transistor Radio
* Signal Injector
2 Transistor Regenera*
5 Transistor Short
* Transistor Tester
tive Radio
Wave Radio
NPN -PNP
* 3 Transistor Regenera* 4 Transistor Push Pull * Electronic Metronome
tive Radio
Amplifier
* Audible Continuity
Tester
* 5 Transistor Push Pull * Electronic Noise
Amplifier
Generator
* Sensitive Pre-Amplifier
Components include: 24 Resistors
21
Capacitors
*
* 10 Transistors
* 3kin Loudspeakers * Earpiece * Mica Baseboard * 3 L2-way connectors
2
Volume
Switches
controls * 2 Slider
*
* Tuning Condenser * 3 Knobs
* Ready Wound MW/LW /SW Coils * Ferrite Rod * 61 yards of wire
* 1 Yard of sleeving, etc.
Complete kit of parts including construction plans.
NEW EDU -KIT MAJOR
1
Total Building Costs
P& P+Ion. 65p. (Overseas Seamed P
£9.99
&
P E3 60)
VHF AIR
CONVERTER KIT
NEW
Inc.
&
WITH VHF INCLUDING
AIRCRAFT
Now with free earpiece and
switched socket. 10 translator.. Latest 6" x 3"
loudspeaker. 9 tuneable
Everyday
Series
Build this Converter Kit and
receive the Aircraft Band by
placing It by the side of a
radio tuned to Medium Wave
or the Long Wave Band and
operating as shown In the
Instructions supplied free with
all parts. Ums a retractable
chrome
plated telescopic
aerial, Gain Control, V.H.F.
Tuning Capacitor, Transistor,
etc.
All Parts including Case ami
£4.35Flans.
ROAMER TEN
MARK 2
Build this
exciting new
series of designs.
E. V. 5. b Transistors and 2 diodes.
W /LW. Powered by 41 volt Battery.
51
Ferrite
rod aerial, tuning condenser, volume control, and now
with 3" loudspeaker. Attractive case with red speaker
grille. Rise 9^ x 61" x 2I^ approx. All parta Including
Case and Plans.
Total Building
costs
P ami
£475
P
&
P + Ins. 50p
Total Building
costs
M.W., L.W., and Trawler
Band, 7 otages, 6 transistors and
Total Build 2 diodes, supersensitive ferrite rod
ing Costa
aerial, attractive black and gold case.
Elise
a
x 3 }" approx.
a
All Parts Including Cue and Plans. P&P +Ins. 50p.
99
23.99
Sr sr
£550 P&P+Ins.65p
Loudspeaker.
All parte including Case and Plans
Total Building
P
Costs
2705
&
P + Ins. 55P
~
.
Contained
Multi -Band
V.H.F. Receiver Kit. 8 Transistors and 3 Diodes. Push /Pull
output. 3" Loudspeaker, Gain Control. Superb
9 section swivel ratchet and retractable chrome
plated telescopic aerial, V.H.F. Tuning Capacitor,
Reeletore, Capacitors, Transistors, etc.W111 receive
T.V. Sound, Public Service Band, Aircraft, V.H.F.
Local Stations, etc. Operates from a 9 Volt PP7
Battery (not supplied with kit).
Complete kit of part. Including construction plans
Self
ECK4
EDU-KIT
Build Radios,
Amplifiers, etc.
from easy stage
diagrams.
E.V. 7. Case and looks as above, 7 Transistors and
3 diodes. Six wavebands, MW /LW, Trawler Band
SW1, SW2, SW3, powered by 9 volt battery. Push
Pull output. Telescopic aerial for short waves. 3"
ELECTRONIC CONSTRUCTION KITS
&
ópp+
output.
.511 parta including case and plane.
LOUDSPEAKER
3 Tuneable wavebands.
P
Ia
E.V. 6. Cue and looks as above. 8 Transistors and 3
diodes. Powered by 9 volt battery. Ferrite rod aerial,
3^ loudspeaker, etc., MW/LW coverage. Push Pull
NOW WITH 3"
£7.95
£11.87
40pP .
POCKET
FIVE
ECK2
wavebands, WW1, MW2, LW, SWl, SW''d, 5W3,
trawler band, VHF and local stations, also aircraft
band. Built in ferrite rod aerial for MW/LW. Chrome
plated. 6 section telescope aerial, can be angled and
rotated for peak short wave and VHF listening. Push
pull output using 800mW transistors. Car aerial socket.
10 transistors plus 3 diodes. Ganged tuning condenser
with VHF section. Separate coil for aircraft band.
Volume on /off. Wave change and tone controls.
Attractive Case in rich chestnut shade with Gold
Blocking. Sise: 9" x 7^ x 4". Easy to follow instructions
and diagrams. Total building costs
Five units including
muter unit to
construct.
Components include: Tuning Condenser: 2 Volume
Controls: 'l Slider Switches: Fine tone 3" moving coil
Speaker: Terminal Strip: Ferrite Rod Aerial: Battery
Clips: 4 Tag Boards: 10 Transistors: 4 Diodes:
Resistors: Capacitors: Three }^ Knobs. Unite once
constructed are detachable from Muter Unit, enabling
them to be stored for future use. Ideal for Schools,
Educational Authorities and all those interested In
radio construction.
All Parta including
Case and Plans
26.99
JIFFY TESTER
Easy to build and operate.
Fits In the pocket. A quick
checker for continuity of
resistors,
chokes,
diodes,
transistore,
circuit
wiring
(not mains) and loudspeakers.
Complete with earpiece, Jack
and
socket
resistor,
plug
capacitors, components. etc.
Complete kit of parts inelol:ne construction plans.
P and Ins. 55p.
Transistors, 6 tuneable waveband., MW,
LW, TrawlerBand, 3 Short Wave Bands.
Receiver Kit. With 5" x 3" Loudspeaker.
Push /Pull output stage, Gain Control, and Rotary
Switch. 7 Transistors and 4 Diodes. 8 section
chrome-plated telescopic aerial. 85 Sensitive Ready
Wound Ferrite Rod Aerial. Tuning Capacitor. Resistors,
Capacitors, etc. Operates from a 9 Volt PP7 Battery
(not supplied with kit). Complete kit of parta including
construction plane.
P & P and Ins. bbp.
7
Li-25
*
*
*
*
*
*
Battery necessary.
Amplifier.
One Transistor Radio.
2 Transistor Regenerative All parts including Loudspeaker,
Earpiece, MW Ferrite
Radio.
3
Transistor Earpiece Rod Aerial, Capacitors, ReRadio
Medium Wave eietore, Transistors, etc.
Complete kit of parta includCoverage.
ing construction plans.
4 Transistor Medium Wave
Loudspeaker Radio.
cal
If5
P & P+
Electronic Noise Generator
E
L,
In e.
ALL PRICES INCLUDE VAT
Callers side entrance "Lavelle' Shop.
Open 10-1, 2.30 -4.30. Mon -Fri. 9-12 Sat.
I enclose g
*
*
for
Name
P+
1
1
I
Address
55p
Nab
Practical Wireless, May 1976
&
Ina. 30p
Keg. No 741,372
Completely Solderless Electronic Construction Kit. Build these
protects without Soldering Iron or Solder.
Crystal Radlo Medium
Electronic Metronome.
Wave Coverage
No
4- Translator Push /Pull
-
P
TO RADIO EXCHANGE LTD.,
6IA HIGH STREET, BEDFORD MK40 I8A
Tel: 0234 52367.
EDU -KIT JUNIOR
*
£3.15
1
PWS76..1
23
-
SUBSCRIPTIONS PRACTICAL WIRELESS
AND TELEVISION MAGAZINES
are still receiving numerous letters requesting subscriptions
to Practical Wireless and Television magazines. For those
readers who are not aware, we regret that our magazines can
no longer be supplied on direct subscription by IPC Limited due to
escalating costs.
This action is very much regretted, but it should not mean that any
reader is deprived of his /her regular copies of Practical Wireless or
Television. Readers should order direct from their local newsagents.
Any readers outside the UK who have difficulty in locating a supplier
should write to the Editor and he will advise them of their local agent.
WE
Grimsby A.R.S.
THE Grimsby Amateur Radio
Society has moved to a new
QTH. The address is now
the New Alexandra Social Club,
Alexandra Road, Cleethorpes.
The meetings are held fortnightly on Thursday evenings at
8 p.m. Old and new members are
always made welcome as is anybody with an interest in short
wave listening, amateur radio,
electronics etc.
If anyone would like further
details, please contact George
Smith, G4EBK, Hon. Sec., 6 Fenby
Close, Grimsby, South Humberside, DN37 9QJ.
RNARS events
following is the 1976
calendar of events of the
Amateur
Royal
Naval
Radio Society, the headquarters
of which, G3BZU, are located at
HMS Mercury, Leydene, Hampshire. If you would like any
further information, contact Mike
Matthews, G3JFF at the above
THE
address.
16 -24th April
HMS Belfast activity period.
GB3RN all bands. 24 hour day
operation. Further details G3HZL
QTHR.
20th June
HMS Mercury Mobile Rally.
28 -30th August
Portsmouth D o c k y a r d-Navy
Days. GB3RN and displays in
conjunction with HMS Mercury
Communications Exhibit.
16 -17th October
JOTA scout camp and Amateur
radio teach-in at HMS Mercury/
G3BZU.
24
NEWS...
NEWS...
NEWS...
Fuse Standards
HE British Standards Institu-
tion has published a revision
of BS 88 now entitled Cartridge fuses for voltages u5 to and
including 1,000V a.c. and 1,500V
d.c. There are two parts: Part 1
General requirements, and Part 2
Supplementary requirements for
fuses of standardised dimensions
and performance for industrial
purposes.
Part 1 specifies general requirements, including characteristics,
construction, performance, and
proving tests for all types of cartridge fuses. Subsequent parts will
give supplementary requirements
in different applications. Part 2
is for industrial purposes, and
specifies fuses most commonly
used in the United Kingdom.
These two parts of BS 88 substantially agree with IEC publication 269. The earlier edition of
the standard has been withdrawn.
BS 88 Part 1 price £5.50 and
Part 2 £3.50 may be obtained
from BSI Sales Department, 101
Pentonville Road, London NI
.
9ND.
BBC
Radio Leicester
Radio Leicester's
medium - wave service is
transmitting from a new,
improved aerial at Freemen's
BBC
Common.
The medium -wave service, on
188 metres (1594kHz), can be received at distances of twenty
miles or so from the transmitter
in daytime, but after dark the
coverage is restricted by interference from other transmitters.
The vhf programme is transmitted on 95 -1MHz.
Radio Societies
Association
N.
THE Annual Convention and
Exhibition of the N.R.S.A.,
which is sponsored by radio
societies in the North of England,
will take place at Belle Vue,
Manchester on Sunday 25th April
1976.
The doors will open at llam
and there will be a large number
of trade exhibitors, as well as
club display stands. A trophy will
be awarded for the best club
stand and there will also be a
variety of demonstrations connected with different aspects of
amateur radio.
Other attractions will include
a Grand Raffle, an Inter -Club
Quiz and a Construction Contest.
Comprehensive talk -in facilities
will be provided on 2 metres
145.5MHz (FM), 145MHz (AM),
and on 144.290MHz (SSB); also
on 4 metres 70.26MHz (AM &
FM). There will be a GB3NRS
HF bands station operating from
the exhibition.
For long distance travellers it
is hoped to offer talk -in through
the local repeaters GB3MP
(ChR6) and GB3RF (ChR7). Both
these repeaters are scheduled to
be on the air before the event,
and there is considerable interest
in mobile operation throughout
the North West.
The N.R.S.A. is a non -profit
making body which relies on the
income from this convention and
the small subscription from
member societies in order to
organize the following year's
event. Further information can be
obtained from the Publicity
Officer: -Mr. Gordon Adams, 2
Ash Grove, Knutsf ord, Cheshire,
WA16 8BB. Telephone:-Knuts-
ford 4040.
BBC
Soo
Radio Medway -
BBC Radio Medway's medium wave service on 290 metres
(1034kHz) is now transmitted from a new aerial at Hoo
and the old station at Gillingham
has closed down.
The vhf service from Wrotham,
on 96.7MHz, is unaffected by
this change.
Practical Wireless, May 1976
RTTY news
THE British Amateur Radio Teleprinter Group announced the start
on 7th March, 1976, of its RTTY News Bulletin service for radio
amateurs.
Initially, the transmissions are made every Sunday according to the
schedule below; later it is expected that more transmitting stations
will be added to those listed.
The material transmitted will include test tapes for machines and
systems plus news of specific RTTY interest.
The licence for GB2ATG is a broadcast, not a communications licence
so transmitting stations will not be able to reply to any calls using
this callsign.
Frequency
Time
1.
1200 hrs
3590kHz
Signal Characteristics
45.45 bauds FSK
170Hz
2.
1230 hrs
144 60MHz
NEWS...
NEWS...
NEWS...
shift
(i) 45.45 bauds FSK,
850Hz shift
(ii) 45.45 bauds AFSK,
Hot news
from Heathkit
Transmitting
Stations
G3I I R,
G3OZF, GW3IGG
G3IIR, G3OUF,
G3OZF
170Hz shift,
2125/2295Hz tones
Summer School
Department of Electrical
Engineering Science
at
THEEssex
University will be
holding its annual Electronics
Summer School for teachers
during the week July 12 -16
this year. Three courses will be
run simultaneously. The "Linear
Circuit Design" course is concerned with the use of transistors
and operational amplifiers in
analogue applications and the
basic circuits of a hi -fi amplifier
are investigated in detail. The
"Digital Circuit Design" course
concentrates on the use of the
transistor as a switch and
develops design using integrated
logic circuits; a digital patch board is used to introduce the
concepts of combinational and
sequential logic design.
"Small Computer Systems" is a
new course which should be of
interest to mathematics teachers
as well as those interested in
electronics; the aims of the
course are to introduce a typical
small computer, the PDP -8, to
investigate how it is used and
to discuss its function in schools.
Further information on the
Summer School can be obtained
from R. J. Mack, Department of
Electrical Engineering Science,
University of Essex, Wivenhoe
Park, Colchester C04 3SQ, telephone Colchester (0206) 44144,
extension 2408 or 2299.
Practical Wireless, May 1976
Amateur Computer
Club
IF you would like to find out
more about the Amateur
Computer Club, send a
stamped, addressed envelope
to J. T. C. Aslen, Club Secretary,
Basildon, Essex.
7 Doordells,
Telephone: Basildon 411125 or
0484-56712.
They have recently published
for a low-cost computer
and they think they will have
working models by the middle of
this year.
a design
Longleat Rally
THE 19th Longleat Mobile
Rally will take place at
Longleat House, Longleat
Park, near Warminster, Wiltshire,
on Sunday June 27, 1976.
As in previous years, the trade
stands will be housed in large
marquees. The rally is to start at
10 a.m. and talk-in stations will
be operational on 160m (1920kHz),
80m (3775kHz) and 2m (145.50 kHz + VFO). Callsigns will be
announced nearer the date. There
will be a walking DF hunt at
3 p.m. on Top Band and there will
be a Grand Raffle. Overnight
camping will be allowed from
6 p.m. on Saturday 26th. Further
gen from Brian Crocker, G3ULJ,
Organiser, 36 Portland Street,
Staple Hill, Bristol, BS16 4PT.
HEATHKIT announce their
"Modulus" system of audio
units. The range comprises
digital AM /FM tuner /2-4
channel preamp /control centre; a
stereo receiver of "medium" or
"high" power; and a 4- channel
receiver "medium" or "high"
power. You build in to your system what you want. Optionals
include FM Dolby CD4
Demodulator and SQ Decoder.
All these items and more feature
in the April /May 1976 Heathkit
Catalogue supplement. Heath
Limited,
Dept.
(Gloucester)
PW46, Gloucester, GL2 6EE.
a
-
Barking Society
HE Barking Radio and Elec-
Society G3XBF/
have recently
G8GPK,
started a new activity dealing
tronics
with all aspects of closed circuit
television. This section is attempting to build its own studio, but
is hampered by a lack of members and may be forced to close.
They feel there must be a need
for a Video club in their area and
have asked us to mention its formation in the News section of
P.W. The society also runs a
Morse Class on Tuesday evenings.
Further details of any of their
activities can be obtained from
J. R. Wiles at Society HQ, Westbury Recreation Centre, Westbury
School, Ripplé Road, Barking,
Essex, IG11 7PT. (Telephone: 01594 4009.)
25
t3.47egao RQ
GELLL47 ALS
F.
G. RAYER
UAL
THIS tuned RF amplifier will be found to provide
quite substantial gain, and is of great help in
bringing weak signals up to a level where they
can be received properly. Even with a sensitive receiver having two RF amplifiers and a number of IF
stages, its can result in the satisfactory reception of
signals which are otherwise virtually impossible to
copy.
With stronger signals, which would in any case be
received satisfactorily, the unit helps to reduce
second channel intereference, which can be troublesome with some receivers. However, its main use is
in improving reception where a poor aerial, or the
low signal strength of the wanted transmissions,
makes adequate reception otherwise impossible.
CIRCUIT DETAILS
Three coils are used, Ll, L2 and L3, Fig. 1. Switch
Si selects the required coil. One section of VC2
(208pF) is used for L2 and L3. For the lowest frequency range Ll, VC1 is also in circuit, giving 384pF
in all. As a result, three ranges as follows are
obtained:-
Range 1-15-- -32MHz
Range 2-55 -15MHz
1.6-5.5MHz
Range
It is of course not essential to provide tuning in this
way. But if a value of about 365pF is used for all
bands, Ranges 1 and 2 will overlap considerably,
while the use of 200pF or so for each band will curtail the coverage of L3 at the low frequency end.
3-
o
+gv
S1c
Off
Receiver
K1
100pF
Fig. 1: Complete circuit diagram of the
amplifier, showing the
method of switching
the coils to obtain a
frequency coverage of
1.6MHz to32MHz.
g1
40673
Ov
(W1761
26
Practical Wireless, May 1976
*
RFC1 and capacitor C5. This will work satisfactorily with receivers having a high nominal aerial
input impedance. With receivers having a low impedance, overall gain can be increased by using an
impedance matching coil, but this would either have
to be tuned in addition to the aerial coils, or be a
broad -band device.
When using the unit with communications type
and similar receivers, it was found necessary to
employ a screened co -axial lead to the receiver. The
power supply is a small internal battery, the drain
being only a few milliamps, depending on the setting
component list
Resistors
R1
68kí2
R2
270g)
25kû Lin. potentiometer
All resistors 1W 10%
VR1
Capacitors
47pF
100nF
C4
C1
10nF
100pF
C2
C5
10nF
C3
VC1 /VC2 Jackson type 00, 176 /208pF gang.
of VR1.
Semiconductors
TO
40673
CABINET
Miscellaneous
Lt, 'Blue' valve type Range 3. L2, 'Blue' valve type
Range 4. L3, 'Blue' valve type Range 5 (All coils
Denco miniature dual purpose). RFC1, RF choke
type Denco RFC5. Jackson type 4832 two speed
drive with knobs. S1a, b, c, 3 -pole 4 -way rotary
switch. 127 x 101 x 51 mm Universal chassis, with
extra 127 x 101mm plate. (Home Radio). Four 12mm
high rubber feet. Two insulated aerial sockets.
Coax socket. Tag strip comprising 8 tags. Battery
clip. Two matching control knobs.
A low -cost and effective screening box and case
can be made easily from a 127 X102 X 51mm "universal chassis" with an extra 127 X 1O1mm flat plate,
which is later attached with self-tapping screws for
the top.
As the coil fixing bushes and core -adjusting screws
Results would be the same, but it is felt that having
three ranges which include all bands from 1.6MHz
to 32MHz in this way is probably better.
Switch section Sla /b Fig. 2 is for coil coupling
windings while the third section of the switch, Slc,
for on-off purposes. An alternative aerial socket
Al, when the unit is
required to tune fairly sharply. Any end -connected
aerial can be used.
Potentiometer VR1 allows amplification to be reduced when strong signals are present, as these might
overload the receiver. This control however does not
reduce gain to the level where no signals can be
received.
Coupling to the .receiver is from the RF choke
is
A2 is fitted for use instead of
B L2
Plan view of the amplifier with the top plate removed. The ganged
capacitor VC1 /2 is driven via reduction gearing to provide precision
tuning.
A1/C1
6 L3
6 L2
6L1dVC1
1W178,1
Fig 2: The three -pole four-way switch S1 is
of the rotary type, and front
panel mounted.
Practical Wireless, May 1976
of the coils project through the bottom of the case,
four plastic feet are required to raise it about 13mm.
First drill one 127 X 51mm member for the front,
and fit the switch, VR1, and drive. The bottom 127 X
51mm flat plate is screwed on, and can be drilled to
take VC1 /2, which is held with one or two 4BA bolts.
Washers or other distance pieces are necessary to
raise the gang slightly, to get it level with the drive
coupling. The capacitor fixing screws must not be too
long, or they will short circuit or damage the capacitor. A final lining-up of drive and capacitor is easy
if the drive fixing holes are on the large side.
Nearly all wiring is completed before the sides and
back of the case are fitted. The back is prepared by
drilling it for the aerial sockets and co -axial outlet
and a clip is made to hold a PP4 b5ttery. When the
back is fitted, one 4BA bolt is used for an earth connection.
27
SK1
A1
Cl
A2
Fig, 3: The schematic
shown here gives the
location of all components, and the wiring
between components
and controls.
Sib
Switch S1a/b /c
Slc
f
WIRING DETAILS
Leads are run approximately as in Fig. 3. The tagstrip is raised on 12mm long bolts. As unnecessary
coupling between gate 1 and drain circuits is likely
to cause instability, G1 is connected directly to VC2.
For the same reason, the drain lead is lengthened
The case is constructed from a single Universal Chassis with an extra
plate. Size is approximately 101 x127x51mm.
28
W177
and taken to the tag holding CS and the RFC, both
adjacent tags being earthed as in Fig. 2. Trl is gate protected, and no special precautions need be taken
when fitting it, provided the soldering iron is earthed
and overheating is avoided.
The coil pins may need scraping, before soldering.
Lengthy heating should also be avoided here, or the
pins may move. Connections told the switch can be
seen from Figs. 2 and 3. All these leads must be
reasonably short and direct.
When the sides and back are fitted, connections can
be made to Al, A2 and the co -axial socket. The
battery is placed with its positive end toward Ll.
Earthing is provided by a terminal, or by the
co-axial lead to the receiver. Having the latter unnecessarily long may reduce signal strength in some
cases.
A frequency scale for the tuning need not be provided, as the amplifier is simply tuned to bring about
an improvement in signal strength. With the unit
switched to the Range needed for the receiver frequency, tuning should be found to peak up signals
considerably. This will be most apparent with weak
signals, or with the receiver AGC off. If the receiver
has a tuning meter, this will show correct tuning. The
coil cores are set to give coverage approximately as
described. Exact coverage is not important, provided
the ranges overlap slightly.
Should whistles accompany reception, especially
with VR1 at maximum gain, Trl is oscillating. This
is most likely when using an unscreened receiver
aerial lead, especially if this is near the aerial connection to the unit. Tuning the booster should be
found to peak up signals or aerial noise but not cause
025
heterodynes or oscillation.
Practical Wireless, May 1976
TAKE
2
No. 74
SNAP MACHINE
DAVID ANDREWS
A series of simple transistor projects, using not more than
*
twenty components.
components list
R1
R2
R3
R4
R5
R6 4.7k0
R7
22k0
100kû
R8
4700
R9
R10 22k0
22kû
22k0
100k0
4700
4.7k0
All +W
10%
LEDI /2 MV5025 (or general purpose LED)
Tri BSY95A
Tr2 BCY71
Tr3 BCY71
Tr4 BSY95A
S1/2 push -to -make buttons
S3
push -to -break button
S4
single pole on -off
Veroboard, PP3 battery and connectors. Suitable
case, about 130 x 65 x 40mm.
THERE have been lots of designs for simple Snap
indicators published. Most, however, suffer
from the problem that indication of the winner
only lasts as long as the competitor presses his
button. For that reason the following design has a
built-in memory which ensures that the winner is
indicated for an indefinite period until a reset button
is pressed.
For the benefit of those who have not come across
a Snap indicator before let's briefly explain the object
and principle of operation. For games of skill
involving two people it is sometimes desirable to find
out who answers the question first. Before attempting
to answer, the person has to commit himself to
answering by pressing a button which lights a lamp
and inhibits the opponent's button and lamp from
operating.
The psychological impact of the Snap indicator
enhances a game's excitement considerably. The
indicator could equally well be used in conjunction
witkt the classical "Snap" card game.
Flip -flop circuit
Inspection of the circuit will show that Trl and Tr4
form a simple flip-flop which becomes cross -coupled
when either of the push-buttons S1 or S2 is closed.
This action illuminates the LED on the side of the
push-button in question and prevents the opponent's
LED operating. This circuit differs from many others
by the inclusion of Tr2 and Tr3 which respectively
act as "latches" to Trl and Tr4. If S1 is depressed
Trl switches on and LED1 lights up. The collector
potential of Trl falls to zero thus preventing any base
current drive to Tr4 inhibiting the other player's
00.°0--0 +9V
S4
S3(push
to break)
R9
RB
470
100k
LEDI
MV5025
Tr2
BCY71
Tr3
ir
BCY71
Tr4
BSY95A
R1
22k
LED2
MV5025
R6
Complete circuit diagram
of the Snap Machine, showing flip-flop Tit and Tr4,
and latches Tr2 and Tr3.
R10
22k
4.7k
OV
S2
o
S1
o
u
Practical Wireless, May 1976
1W0971
29
® Break in strips
Direction of strips
Cathode
S1
LEDI
Pw TE CHNICROSS
..
.
UiIE No.13
III
.E
7
.. .
..11
e
..
.18
. . ....
..
..... . .
1
8
2
3
,
4
9
10
12
14
15
20 23
17
19
25
24
To
BCY 71
BSY 95A
S4
Battery
connections
for PP3
FK01501
Component layout of the Veroboard panel and wiring to the switches
and LED'S. The size of the board is for guidance only.
16
21
22
S3
13
.
26
27
28
ACROSS
Grateful for this lack of fidelity? (9)
8 Spoken part chorally introduced? (4)
9
Steamiest form of radio? (8)
10 Untrue of Dylan's radio play? (6)
12 Drily cut off but I shall shortly be heard! (4)
14 Gets the message and sticks to the script! (5)
15 Cine movement in southern France? (4)
17 Demand precision in complex acting? (5)
19 Coverage of the first garden programme? (4)
I love her broadcasting manner (5)
21
22 River said to be in slow motion (4)
25 Set off because of the French component? (6)
26 A tuner in civil aviation? (8)
27 One piece heard from the deepest bass? (4)
28 He sings of a drink and a lake (5, 4)
3
circuit. The potential at the positive end of LEDI
also falls towards zero and this provides a source
of base current for Tr2 which is a PNP device. The
collector voltage of Tr2 rises towards the positive
supply rail providing an alternative source of base
current to Trl through R2.
If the player's finger is removed from the pushbutton this alternative supply of base current keeps
Trl switched on and LEDI illuminated. At the same
time the circuitry around Tr4 and LED2 is still
inhibited, the only way to switch LEDI out and reset
the circuit for another attempt is to break the circuit
between the emitters of Tr2 and Tr3 and the positive
rail, with the normally closed pushbutton S3.
DOWN
1
2
Board layout
Provided the layout is carefully followed there
should be no problems in the assembly of this circuit.
Use normally open push- buttons for S1 and S2 and a
NORMALLY CLOSED one for S3. It is important to
connect the LEDs with the right polarity. The
CATHODE of the device should be connected to the
collector of its driving transistor. Using the specified
devices the cathode end can be identified by a very
small indent on the base of the red plastic or by the
fact that there is a wider shoulder on the. top of the
cathode lead -out wire. When using other LEDs check
the polarity carefully.
30
4
5
6
7
11
12
13
16
18
How to get on without feedback? (9)
Programme that takes the broader view? (8)
Toy with this in Children's Hour? (4)
A giant in Welsh programmes? (5)
& 20 Down She's on the air fitfully (6, 6)
Actors gloomy over this? (4)
The language you hear on Irish radio! (4)
Its creation may be quite a project? (5)
Welcome the end of transmission? (9)
An impressionable comic? (8)
Pitch of an oscillating note? (4)
20 See 6 Down
23 Kind of breakthrough the talkies made? (5)
24 He mustn't miss a word! (4)
25 A bit of percussion in our hearing? (4)
FOR AMUSEMENT ONLY
ANSWERS NEXT MONTH
Practical Wireless, May 1976
SPECIAL
PRODUCT
REPORT
BI- PRE-PAK
5upEr Spurl(
CAPACITY
DISCHARGE
IGNITION KIT
IN case you do not feel like wading through this review to
the very end we will have the conclusions first! This kit
is easy to assemble and to fit to a car. It worked first time
and starting the car is much easier now, especially in cold
weather. Is it a good buy? At £7.96 -i 8% VAT it certainly Is!
The circuit employed is similar to that which appeared in
PW in June 1971, repeated in June and July 1972. However
there are a few refinements which are very much worthwhile,
all concerned with extra reliability. A two -transistor oscillator
working at an audio frequency uses the primary winding of a
transformer, the secondary feeds a bridge rectifier producing around 350V DC output. This is applied to a thyristor,
the gate of which is triggered by the car's contact breaker on
the distributor. The 350V pulse is fed via a 1NF capacitor
to the primary of the coil. In case you are worried about 350V
being applied to the 12V coil it should be pointed out that
350V is roughly the back voltage developed by the primary
winding when the 12V supply is broken by the contact
breaker, the basis of the ordinary ignition system.
INFO
The general information sheet supplied with the kit tells me
that a Mr. Kettering was responsible for the original system
some 60 years ago, so I've learned something! This sheet is
full or useful information but unfortunately it is poorly
reproduced in a very small type face, the explanatory diagrams being almost unreadable. Bi- Pre -Pak are not alone in
this sad habit of neglecting the all- important "gen" accompanying electronic equipment generally and kits in
particular. It may seem to the seller to be an economy,
saving a few pence in this manner, but I can assure all those
guilty that they are making a big mistake. The second information sheet supplied deals with the assembly of the kit
and installation instructions. This is better produced but
even so the circuit diagram was broken up in parts due to
poor reproduction. Mr. Davis of B -P -P has assured me that
this matter and a few spelling errors are being attended to.
However, it must be said that the printed .circuit board is
one of the best ever seen. The amount of information printed
on the board makes the aforesaid circuit diagram almost
superfluous! The PCB was assembled in a couple of hours,
without going mad. The ends of all component leads were
scraped clean whether they needed it or not. An old habit,
but it pays off, ensuring a good soldered joint every time.
Little sketches of the transistors, diodes and the thyristor on
the circuit diagram and the PCB eliminate any possible
error here when it comes to wiring them in.
Practical Wireless, May 1976
During assembly the PCB was laid across the open top of
the die -cast aluminium box, a great help. This box may seem
to be rather extravagant, representing a fair part of the cost
of the kit, but it does have an excellent seal all round, rather
important considering the muck that can be found in the
engine compartment of the average car! To aid the sealing
a piece of thin plastic sheet was interposed when the lid of
the box was finally screwed down.
ANTI -THEFT
To my mind the biggest feature of the kit, not sufficiently
underlined by B -P -P, is the ability to switch back to normal
ignition at any time thus eliminating that fear in the back of
the mind that the electronic ignition might let you down one
day! It is important to note that if the switches are placed in
opposite positions the car is totally immobilised, which is
much easier than removing the rotor from the distributor!
These two switches are mounted on the PCB and used to
mount the board on the lid of the box. The neon lamp protruding through the lid is one of those little "extras" that instil
confidence, indicating that the unit is producing the 350V
required, further confirmed by the high pitched whistle from
the oscillator indicating that all is well.
INSTALLATION
On applying 12V from a car battery in the workshop,
nothing happened! No current was being drawn by the unit.
A check revealed that the fuse had been omitted' This is a
piece of fuse wire soldered across two points on the PCB,
thus saving a fuseholder. The fuse duly fitted, the unit worked
at once producing the 350V output at the rectifier. The PCB
can be wired for positive or negative chassis but it should
be noted that the black wire goes to the chassis regardless
of the chassis polarity. The PCB is not electrically connected
to the box so this lead must not be omitted.
The unit was fitted to a Triumph Herald 12/50 of 1965
vintage and tested during the very cold spell in February
when temperatures were below freezing for several days on
end. The box was bolted to the left -hand vertical panel
continued on page 60
The photograph in the heading shows the printed circuit board which
is fitted to the lid of the die-cast box by the locknyls on the switches.
As can be seen the PCB is well annotated. The zig -zag lines are the
alternative links for positive or negative chassis connections. The
two transistors are mounted vertically at the extreme righthand end
of the board.
31
AF Signal Source
W. MOONEY
rapid decrease in the price of CMOS (4000
series) digital integrated circuits, and the
THEamazing reduction in quiescent power consumption compared to the popular 74 series, makes
experiment with these devices a tempting proposition. Quiescent power consumption is of the order
of lOnW per gate for the 4000 series and is therefore
negligible, whereas consumption by the 74 series is
about 10mW per gate. Despite conflicting requirements of fast switching speed and low power consumption, these devices will still work well up to
CMOs
n,.
10,
10MHz.
The signal source described here, uses only one
IC which contains two 3 -input NOR gates and an
inverter. The source provides a square -wave of about
1kHz at a voltage of 99% of the battery voltage.
Two outputs are provided, one via a 1µF capacitor
which should give a good square wave into high
impedance loads, and a second output via a 100pF
capacitor, picking off the RF harmonics for signal
injection.
The current drawn from the battery is less than
30µA and increases with the application of a load
to the output. The device will continue to work until
the supply voltage drops to below 3V, when the off
load current will be about 1011A.
Power consumption
In a normal N or P channel MOS gate as in Fig. la
the quiescent power consumption is high because a
load resistor is used. Therefore in this instance when
the output is in the low state a current must flow
through the resistor in order to decrease the output
voltage. This resistor must be fairly low so as to
drive the following stage when a low output is
required. But if too low, the current required to
produce a low state will be too high. A compromise
is therefore arrived at. If the load resistor is replaced
by a MOSFET of opposite polarity (Complementary)
4'
on
to the lower MOSFET as in Fig. lb the need for such
a compromise is obviated as this load fulfils both
requirements.
In the high output state the lower MOSFET
switches off becoming, in effect, a high resistance of
about 101351 and the top MOSFET becomes a low
resistance of about 300f1. When a low output is
required the resistors effectively change place, the
upper MOSFET switching off and the lower MOSFET
switching on. In the complementary MOSFET circuit
(CMOS) the power consumed in the high or low
state is therefore negligible and the great majority
of the power is consumed during switching.
For a brief period during the switching action both
MOSFETS will be equally on and will have a relatively low resistance. At this instant the current
peaks to typically 1.5mA with a 10V supply rail.
When the CMOS gate is in a normal digital environment carrying step pulses, the power consumed due
to this effect is practically zero. The consumption is
then purely due to the capacitance of the load,
typically 5pF per gate.
Vdd
Vdd +
i
P
channel
Outpu
Input
-l--
N
In put
channel
(a)SIngle ended output
Vss
N
(b) Complementary output
channel
la:: A normal N
channel MOS gate with
a single ended output.
Fig,
lb: A similar
device to that shown
in Fig. la, but with the
load resistor replaced
with a P channel gate.
This now forms a
complementary output.
Fig.
Vss
FK1S8
32
Practical Wireless, May 1976
Vdd
* components list
+Q
n n n n n n
14
13
12
11
I
I
10
9
I
Resistors
R1
R2
10MÛ
10MÛ
All resistors 10% }W
R3
R4
1MÛ
see text
Capacitors
Cl
C2
100pF SM
100pF SM
C3
C4
100pF SM
1uF 50V elect.
Semiconductors
IC1
CD4000
Miscellaneous
u
1
Si, miniature slide switch. Aluminium
u u u u u u
2
3
4
FK159I
5
6
7
Vss
Fig. 2: Internal configuration of the CD4000. Gates 'a' and 'b' are
NOR gates and 'c' is an inverter.
Total power
The total power consumed (Pt) by a particular
gate carrying regular step pulses is therefore the
sum of the quiescent power (Pq) in the high or low
state, and the switching power. The switching power
is dependent on the frequency (f), the voltage difference between the high and low states (approx. the
supply voltage Vdd) and the capacitance of the load
(C). Bringing these together we get:
Pt= Pq +CVdd2f
This is arrived at from the familiar expression for
the energy stored in a capacitor 12CV2.
In the source described here the conditions are
somewhat different as the inputs to both gates are
part of a timing circuit. This circuit slows down the
transition through the high current portion of the
transfer characteristic, giving a higher current drain
than would be expected from the above expression.
However at a maximum of 30µA it still compares
very favourably with an equivalent circuit using
discrete bipolar devices.
box 76x
50 x 25mm type AB12, available from Home Radio.
Printed circuit board 45 x 25mm. Three 3mm plugs
and sockets. Three 1.5V cells, type D23.
the high state. As Cl is discharged, the input to
(a) will follow this increase causing the output of
(a) to drop. It will now remain low until Cl charges
through R1 to the point where the output of (a) goes
high once more and the cycle repeats. At the times
of the cycle when the output of (a) or (b) drops to
a low state the associated capacitor will be charged
up and this charge results in a negative voltage
appearing on the following input. A lucky spin -off of
the input protection circuitry now occurs as this
negative potential forward biases certain diodes thus
S1
C3
+
+l1-.pHigh
1}IF 50V
C4
B1
II--o Low
4.5V
1O0pF
Common
FK160
Circuit operation
The internal layout of the CD4000 IC used in this
circuit is shown in Fig. 2, the parts marked (a) and
(b) are the NOR gates and (c) the inverter. The circuit of the oscillator is shown in Fig. 3, all inputs
to each gate are strapped together, the operation
now being the same as that of the inverter where a
low input produces a high output and vice versa.
The circuit will be recognised as a multivibrator
type of oscillator, the frequency determining components being Cl /R1 and C2 /R2. In this circuit C1=
C2 and R1 =R2, thus giving a squarewave of equal
mark /space ratio.
Circuit operation is best understood by freezing
the cycle at a point in time when the output of
gate (a) has just jumped from zero up to nearly the
supply voltage. The voltage on the input to (b) will
follow this rise since Cl is discharged and the output
of (b) will now be zero. The voltage on the input
to (b) will slowly drop towards zero as C2 charges up,
and at some point (about 40% of the supply voltage)
will cause the output of (b) to jump quite rapidly to
Practical Wireless, May 1976
3: The above drawing shows the complete circuit of the oscillator.
With the component values shown, the output frequency is about 700Hz.
Fig.
quickly discharging the relevant capacitor.
The output from gate (b) is passed through the
inverter which isolates the oscillator from the load
and squares up the waveform. The supply line is not
decoupled as it is quite unnecessary and tends to
make starting difficult by removing the switch-on
kick. No specific arrangements have been made for
starting but should the oscillator stop for any reason,
simply switching off for a few moments, and then on
again, will usually start the oscillator running.
Construction
The device is constructed in a ready made
aluminium box measuring 76 X 50 X 25mm. The PCB,
Fig 4 switch and terminals were attached to the lid
of the box as is the power source which consists of
three 1.5V cells, type D23, connected to give over
33
age voltage are equal. This property was demonstrated with a prototype when the battery voltage
was found to be 4.8V (20k ohm /Volt meter), the
output indicated on the AC range was exactly 2.4V
RMS.
Some form of potential divider should therefore
Fig. 4: PCB showing foil side to the left, and component overlay to
the right. The board is shown full size.
4.5V when new. These small cells are not very
popular but a little searching is worth while as they
offer a considerable saving in space, being only about
lOmm in dia. and 30mm long. A long life is expected
of these batteries and they are therefore glued
together and then to the case, making the connecttions by direct soldering. If it is decided to use
mercury cells, direct soldering should be avoided for
safety reasons.
The IC was found to be remarkably robust as the
inputs are protected by an array of zener diodes to
prevent static build up. However in the interests of
good practice the soldering iron should be earthed
and precautions taken to prevent personal static
build up. The timing capacitors are silvered mica
but any low leakage type will do. The output capacitors should have a suitably high working voltage if
work with valve or high voltage transistor equipment
is envisaged.
The source in use
The output frequency of the device with the component values given here is about 700Hz. The square wave is quite good with harmonics extending well
into the short wave region. The output voltage is
dependent on the supply voltage and the device will
work well down to below 3V. Under 3V, however,
starting becomes increasingly difficult. The quiescent
current consumption at 3V is less than 10í%A.
The device has been used for fault finding in AM
receivers and audio amplifiers, although the use of
a square -wave generator does not end here, especially
if an oscilloscope is to hand. For example, the action
be used before injecting the signal into the more
sensitive stages of audio amplifiers, otherwise serious
overload will occur giving misleading results. A
simple attenuator as shown in Fig. 5 will be adequate,
the value of R4 being altered as required. For
example with 2.4V input and R4 =1kf2 the output
will be 2.4mV. Some levels to expect when dealing
with AF stages are as follows:
3mV
Output from magnetic cartridge
80mV
Output from ceramic cartridge
300mV
Output from crystal cartridge
0.5mV
Output from cassette replay head
100mV
Input from, tape, tuner, or aux
Although it should be remembered that the battery
life will be reduced by applying heavy loads to the
source, it is possible to drive an 812 loudspeaker
directly although this hasn't been tried for more
Pw
than a few seconds.
BOOKS
RECEIVED
RADIO CONSTRUCTION FOR AMATEURS
By R. H. Warring
Published by Pitman Publishing Limited,
Pitman House, 39 Parker Street, London WC2B 5PB
120 pages 21 5cros x 14cros.
Price £2.50
THIS book caters for both beginner and the enthusiast
with some electronics experience. It sets out the
theory of radio transmission, describes working
components and circuit construction and provides over
working circuits. Chapter headings included are: Crystal
Sets, More about Tuned Circuits, Transistors, Bias and
Stabilisation, Regenerative and Reflex Receivers, FET's and
IC's. etc.
30
PRINCIPLES OF TRANSISTOR CIRCUITS (Fifth
Edition)
By S.W. Amos
Published by Newnes-Butterworths,
The Butterworth Group, 88 Kingsway,
London, WC2B 6AB
320
pages 21cros x 14cros
Price £3.20
THIS Wireless World book has been updated quite
extensively from the 4th edition by the inclusion of
information on field- effect transistors and the
expansion of the treatment of switching circuits. Chapter 1,
Semiconductors and Junction Diodes deals with the
basics of semiconductor physics and the principles of
Fig. 5: The output amplitude of the Signal Source may be a little high
for some purposes, and this simple attenuator should be used when
necessary.
of tone controls and various filters can then be
observed directly. One fundamental property of a
symmetrical square -wave is that the RMS and aver34
transistor operation. Following chapters include such
subjects as Common -base and Common -gate Amplifiers,
Bias and DC Stabilisation, Large Signal AF Amplifiers,
IF Amplifiers, Pulse Generators and Further Applications
of Transistors and other Semiconductor Devices.
Since Volume 1 was published back in 1959, Principles
of Transistor Circuits has been regarded as a standard
text book by schools and colleges and this latest edition
brings this respected work right up to date so that it will
still be acceptable as a standard course text.
Practical Wireless, May 1976
DOM"
A PROFESSIONAL DEAL
FOR AMATEURS
`ORDERS BY RETURN OF POST "NO QUIBBLE REPLACEMENT PART SERVICE
"QUALITY. BRANDED PRODUCTS 'FREE UPDATE INFORMATION SERVICE
TOOLS
SEMI -CONDUCTOR DEVICES
IN 4001
IN 4002
IN 4003
5p
1.OA bridge
06.10+
LP 1173
LP
eel
6peal+s
1184/2
LP 1185
LP 1186
6p ea.)
E6.58
E4.50
E6.32
05.15
-
LP 1400
milling and reaming tools.
Drill & kit £9.50 +
£4.75 +
Kit only
MULLARD MODULES
RECTIFIERS
The handy EXPO 12V d.c. drill is supplied
complete with drill kit containing 4 small drills,
two spare collets, two cutters, wire brush,
soft buffer, grindstone and 9 various
1.65
1400V1
1200V1
s
16A
1800V)
s
205
1200V1
1600V1
2-OA
32p
48p
70p
72p
+
+
H
H
H
+ H
+
H
H
+
H
H
H
90p+
H
ORYX 60W SOLDERING IRON
TRANSISTORS
(
Temperature can be altered
between 200 -400°C.
Iron 240V £6.90
£2.80
Stand
+
+
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Build yourself a
BIG SOUND amp
s
s
ISO -TIP CORDLESS IRON
Mains and 12V d.c.
venions available
£11.50+ s
DE- SOLDER TOOLS
Three high- suction models
£6.20 + s
SR2
£5.20+ s
SR3
£4.80 + s
SR3AS
at budget price
Spare nozzle 60p ea. +
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,9saal
ea
Sim. to
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HP7
None
HP11
HP2
*
*
High performance
For 2 & 4 stroke engines
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'Crisper' throttle response
Reduce battery drain
*
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50
BFy
51
BEY 52
2N 3055
2N 2646
TIP 2955
TIP 3055
BC
35
*
*
*
*
charge
cur. ImA)
50
E1.10
100
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200
£1.80
s
400
s
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s
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+
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E1.55
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TBA 231
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TBA 800
TBA 8100
TBA 820
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s
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-
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s
lip
H
1op H
12p H
10p H
9p H
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13p H
14p H
:62p
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ZN 414
ZN 424
741 Op-amp
747 Op-amp
(Duel 7411
748 Op.amp
555 TIMER
556 (dual 5551
HA 1156
(similar to
MC 1310P)
H
36p H
40p H
-27p
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H
65p
s
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10 for £1.50
H
BRy39
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56p s
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C1.60 H
72p
ORP12
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40p
s
72p
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25 1034E
H
E1.30 H
E1.00 H
E1.30 H
E1.18
-E4.70
s
-
s
BOOKS (z)
Complete kit with
assembly instructions
Hi -fi hints and tips
Overseas orders £34.50
S.A.E. for full spec.
BATTERY
'SAMOS' CASES
ELIMINATOR
Towers international transistor selector
38p ea.
£2.95 ea.
Electronic circuit design handbook
must for electronic enthusiasts
£4.50 ea.
s
50W x 50H x 100D
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S4 50W it 75H x 125D
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£1.31
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S6 150W x 75H x 125D
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+
s
57 200W x 75H x 125D
£219+
s
SPECIAL OFFER!
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a
PVC steel cases
S1
DORAM'S NEW CATALOGUE
THE AMATEURS GOOD COMPANION
-
Low -cost blue cover and white base
Switched output 6,
7.5 or 9V at 250mA.
D.C. pos. or neg. earth
+
s
+
s
+
s
+
s
£1.68+
s
!
If catalogue ordered simultaneously with order
for SAMOS cases - case price less 25%
"The Doorway to Amateur
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An Electrocomponems Group Company
NAME
ONLY
60p
Overseas orders add 18%
Cash with order. Cheques/Postal
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until Aug. 1976.
Free up -date service
Practical Wireless, May 1976
MVR 15
LM 339K
7805
7812
7815
7824
s
18p
2N 3819)
BF 180
r
Orden to Doram Electronics Limited.
P 0. Box TR8, Leeds, LS12 2UF
Small order handling charge of 40p
for orders under E3.00
E1.55
(Similar to
type required
All pricer are ex -VAT
If affixed with s add 8%
II affixed with H add 25%
2 - zero rated
Package 6 posting free
for orders over E3.00
-
141
s
CONDITIONS OF SALE
MVR12
s
61p
2378.
E1.10
E1.55
T05 Rag '
MVR 5
s
£1.14 s
CS 715
Triple Op -amp pre-amplifier
Power 'Darlingtons'
Modern styling
25W per channel into 8 ohms.
£3.15+
I.C.'s
s
62p
94p
BC 238C
Neg. earth or pos. earth
£15.00
.
TIP 32A
2N 3819
FEATURES
ELECTRONIC IGNITION UNIT
BP/
TIP31A
As featured
in 'ETI' Oct. 75 edition
£2.70
12p
20p
19p
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2TX 107
ZTX 108
ZTX 109
A
s
nom.
capacity
0.5Ah
1.2Ah
2.0Ah
4.0Ah
lip
BC 109
ZTX 300
ZTX 500
MIE 340
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RECHARGEABLE CELLS
,i,
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ocios
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r,
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ADDRESS
POST CODE
I
enclose 60p. Please send me by return my Doram Catalogue.
(Overseas orders except B.F.P.O. please add 30p for post and
I
I packing surface only ).
35
TANGENTIAL BLOWER HEATER
2KW can be
for
two
switched
240V
speeds and 1KW Robust and efficient. Aperture 71" x 11 " size
overall length 10". Price
£4.25 plus p. & p. 75P.
DIGITAL DISPLAY INDICATOR
by KGM, Type M4. window size 1 " wide,
1f" high, depth II ", height 31" plus front
flange (I" top and bottom). This is an
Acrylic edgelit unit illuminated by
12V
flange type bulbs (as our min. lamp type D)
Currently sold at £1400 plus, our price
£3-OS Inc. lamps, plus p. & P. 35p.
A
B
D
C
F
E
MINIATURE LAMPS
Size
Size
Type (Die.) Volt /Curr.
Type (Die.) Volt /Curr.
D
A
3MM 2 -5V 360 MA
3MM 5 -6V 60 MA
5 -6 60 MA
B
IMM 4V 250 MA
4MM 6V200 MA
E
5V60 MA
6.3 200 MA
12V 40 MA
I4V 40 MA
12V 100 MA
F
4MM 2.7V 60 MA
14V 75 MA
12V 160 MA
28V 40 MA
14V 80 MA
C
5MM 28V 40 MA
G
Small telephone lack type 6 or 24V
Price: Types A -F £4.00 for 25. 50 and upwards 13p each
Type G 45p each. p. & p. 200 per order.
RIBBON CABLE
way side by side P.V.C. 7 strand red- green -blueyellow (miniature) 50 metre reels Ea -50. 250 metres £20
P 6 P 70p 50 metres. £1.50 250 metres.
4
50p.
SPRITE "PANCAKE" FANS
B
Type C miniature no. 83 -132,
size 1" x 1" x 1 " high, plus
tags, 5 a 250V. Price 30p
each (min. 5) Lever 1" long
19/16" long either type Sp
each, plus p. & p. 20p.
Similar to "Muffin", physically
smaller, drawing only 9 watts
but still giving extremely high
efficiency
SOLDER GUN BY ETP
240V for instant heat and speedy soldering. 100 watts,
built in spot lamp. Price £3.50 plus p. & p. 50p.
BENDIX MAGNETIC CLUTCH
E
A superb example of Electromechanical The main body Is in
two sections. The coil section is
fixed and has a lin sleeve. The
drive section rotating on the
outer perimeters. The uniting
plate has lin ID bearing concentric with main section and
18 -tooth
cog
wheel. When
energized transmission is extremely powerful, 24V d.c. at
240 MA. Our price lust £2.70
plus 30p P. & P.
& 2 oz. copper size 43" z 37"
First grade material.
thickness double sided ' /a2 /,a /a. /,," single sided
& '/a," all types £10 per sheet. Carriage £2 one
sheet plus 50p additional sheets (G.B.).
" "' "'
THUMBWHEEL EDGE SWITCHES
P. & P. 75p.
ARROW SWITCH
per pair, p.
(Plessey) ten position
0-9 (single pole ten way)
modular, any number may
be banked. Contact rating
2a. A.C. or D.C., colour
black, size overall 5258
high x 12 wide x 49 mm
deep. P.C. pitch 156.
Price £1 -S0 per unit, end
mounting cheeks £1.00
L p. 30p any order.
PROGRAMME TIMER
1111101;.0!.
pull. 21"
type MM6 31b
x 1"
z 11 ".
MEM LIMIT SWITCH
Snap action 5 amps at 240/410 A.C. size base 31" 11"
a1.1" plus heavy duty roller plunger 11 " eat. or 1 " when
compressed. Very robust for tireless operation,
weather proof. Price £2.20 plus p. & p. 25p.
10 K.W. ISOLATION TRANSFORMER
Prim. 200 -240V sec. 120- 0-120V, size 18 " z 15" a 26"
high, weight approx. 2501bs. Price £110 inc. VAT
delivery charge at cost.
D ISC
-
plus p.
317
)
& p. 15p.
Tel: 01 -723 5667 01 -402 5580
WE ARE OPEN 9-6 MON. TO SAT.
PERFORMANCE
- --
EDGE CONNECTORS (CINCH)
and 364 EDGWARE RD.,
LONDON, W2.
Capacitor
Discharge
EASY COLD START
50p.
Single contact sockets. 27 way .15, can be cut to
length, moveable and mounts. 10 pieces (minimum)
for £4.00 plus p. 6 p. 25p.
companies and Educational Departments, it is no
longer practical to Invoice goods under £10. Therefore,
please remit cash with orders below this amount.
MAXIMUM ECONOMY
spindle
". Price £3.50 plus
Matched pairs, Pioneer type 174 similar to oro 12
resistance 1K to 40K, dia 1 "" with 1 " flanges. £1-S0 for
two pairs (minimum) 10 or more pairs 50p. per pair
Puce
Whilst we welcome official orders from established
IGNITION
MAXIMUM
1
LIGHT DEPENDENT RESISTORS
11b.
ALL PRICES INCLUDE V.A.T.
COMPONENTS LTD.
31 " x 21 " and
die.
with
magnet,
Complete
normally closed, 3 amp
vacuum sealed. 11 "" long
, ",
dia.
10 for £2.50, 50 for £1100,
100 for £1000 plus P. L P.
30p. for 10 to 100.
& p. 25p.
MAINS SOLENOIDS
ELECTRO- TECH
L p. 70p.
SYLVANIA SWITCH
1
F
screws. Length of arm,
21 " 240V. a.c. Pull at coil is approximately
£1.25 plus p. & P. 2Op.
p. & P.
34' x
P. & P.
1
This little unit gives
vertical lift of approxlin.
through
imately
hinged "elbow ". Bracket
fixing
2
incorporates
RELAYS
Octal base 2 C/O 6 amp contacts
following voltages: 12V a.c. 48V d.c.
110 d.c. 230 a.c., all £1 -25 each plus
base 15p postage and packing 150.
11 -pin 3 C/O 6 amp contacts, following
voltages: 115 a.c. 48 d.c. 24 d.c. all
at £1.50 each, base 15p plus 15p
p.
cam operated
a.c., high Torque,
approximate overall size
pull. 11" x 11" x ".
Travel ". E125 each,
plus p.
bank.
micro switches, infinitely
variable switching 240V.
Speed 15 r.p.m. (4 secs
per rev). Price ES-95 plus
240
Travel 1 ". £1 -S0 each,
plus p. S p. 25p.
240 a.c. type MM4 21b
p. A p. 30p for 5.
a
12
SHADED POLE GEARED MOTORS
110 r.p.m.
SOLENOID BY WESTOOL
240 a.c.
ò
6 DIGIT 24V d.c. COUNTER
Non re-set 3 watts, size 11" o 1" x
13/16 ". Brand new. Plastic encased.
Price £2.25 plus p. & p. 25p.
NORPLEX COPPERCLAD FIBREGLASS
1
fuss.
34" z 11 ". (Large quantity available, special quotations). ONLY
£I-SO plus p. & p. 50p.
D
Type E no. 83 -131, 10 a 250V
size 1}" x 1" x 1" high. 30P
each (min. 5) plus lever 11"
long, Op each plus p. & p. 20p
each.
'/"
with minimum
115V 50 Hz can be used in pairs
from 240V a.c. dropping resistor
supplied for 50p. Size: 31" x
C
Type D similar to Type C,
but with tags underneath,
uses same lever as Type C
or can be banked horizontally and double lever (as
shown) supplied at 12p.
Prices as type C.
outlet approx. 21" x 21 ", overall width
5 ", overall dia. 51 ". Price £475 plus
VISIT OUR NEW BIGGER AND
BETTER SHOP -NOW OPEN
RANGE
AT
ESTING ITE
OF INTERESTING
poly -planar
20 -Watt
Full Range Speaker
Completely replaces the
conventional cone speaker
Super -thin construction
permits new installation ideas.
40 watts peak. Frequency range: 40 Hz -20 KHz
85 dB /M for 1 watt electrical Input. Input Impedance:
ohms. Operating temperature range: -20 °F to +175 °F. Size
(WaD%L): 17/16 " x 11.3/4" x 1411/16 ". Weight: 19 ounces"
Power capability:
I
Professional photoelectric ignition using L.E.D. light source and reflective disc. This
machined aluminium disc gives a timing accuracy far superior to other methods and is
simple to fit. Unit housed in diecast box 4/b " 3%" o 2h" Pria £18.80 (Kit £16.801
State car /model /measurement across cam lobes.
SYSTEM II
Contact breaker model as above less sensor. Price £12.80 (Kit £10.001 M/C Twin unit
Prim £15.00. S.A.E. for descriptive leaflet ALL UNITS IN STOCK. Mail orders to
cot Electronic Systems Ltd, 275 Vale Road, Ash Vale, Aldershot, Hams.
Demonstration /Callers to Hillside Motors, 292 Carshalton Road, Carshalton, Surrey.
telephone 01.642 9973.
-
36
needed. These fans are 115V.
50Hz drawing only 14 watts
41 " x 41" x 11 ". They can be
coupled in pairs for use on 240V
dropping resistor can be supplied
for 50p. ONLY £0-SO plus p. & p.
A
20P P. & P.
240V powerful, efficient by Universal
Electric. 3,100 r.p.m., inlet dia. 4 ",
SYSTEM
As used in computers and other
installations where silent continuous efficient cooling Is
(NON ARC)
Types A/B no. 83-112 n/o or
n/c as desired, rating 5 a
240V, size 11 "x1 " x1 "high.
Can be stacked horizontally
or vertically, In this mode,
top switch can operate
multiples. Type A has
straight through plunger,
whilst Type B is encased at
bottom. Makers price approx.
£1.40 each, our price 45p
each (min. qty. 5) plus 15p
per roller (as shown) plus
CENTRIFUGAL BLOWER
Press
off,
on /press
single hole fixing SP
ST size 11" x 1 "" prestle
extenda 1 ". Rated 21
amps. Robust. Price
for 5 (min qty.) £1.75.
10 or more 30p each.
MUFFIN "PANCAKE" FANS
CROUZET MICRO SWITCHES
Sensitivity:
8
£850 each Stereo pair £16.50
INCLUSIVE OF VAT AND POSTAGE
web europa
P.O. Box 9, Ruthin Clwyd
Practical Wireless, May 1976
GOING BACK...
1970
60
`Hpfterp' ikettiber
IHAVE received a letter from
one of our younger Going
Back enthusiasts-John Nar-
borough, aged 16, from Uckfield
in Sussex.
He tells me that he has quite a
collection of vintage radio equipment and during his three or four
years of being a PW reader,
prompted by reminiscences from
his dear old dad who used to
dabble in radio in the '20s he has
become extremely interested in
the earlier days of wireless.
He says he is finding-much to
his mother's delight-that it is
becoming increasingly hard to
find items of equipment (that do
not have misguidedly high price
tags) with which to "clutter" up
the home. Nevertheless, John considers that he has one or two
prizes in his collection.
John'would like to know if any
other Going Back readers could
help him concerning the item in
the two smaller photographs. The
set is built into an oak cabinet
which has a drop -down front.
Three valveholders are mounted
at the top with filament rheostats
below. Also included are the
usual tuning and reaction controls, three sets of coil terminals
50
20
30
40
COLIN RICHES
and a reaction control for some
external piece of equipment -possibly a frame aerial-even though
there are AE and E terminals on
the panel. The wiring (it's a pity
but a few of the components are
missing) indicates that the set is
probably an early '20s' design and
there is a transformer wound
"like a coil in cylinder form ", the
core of which comprises individual iron wires. Under the detector valve socket (centre) there
is a screw -in variable grid leak
and coil changing system of plugs
and sockets. An engraved "wiper"
type switch gives ranges from 200
External view of the 'mystery' receiver.
to 3000 metres. Each valve holder
has switches for its individual
power supply.
John passes on a useful tip here
-he only managed to decipher
the wording on the controls by
rubbing the ebonite panel with a
cloth dipped in turps. This reveals
the mark where the lettering
used to be-but only while it is
drying.
What John would like to know,
if anyone would care to drop him
a line is who was the manufacturer and where do coils /frame
:
aerial fit?
The set does not look home brewed bit could be a "limited
quantity" set. The DPDT switches
are made from a commercial
front knob and a home-machined
contact system of brass strip.
The larger picture shows some
of John's collection. Creeping off,
the picture at bottom right is a
Brown Microphone Amplifier
which he has had working-even
though the tone is rather shrill.
Anyone interested can contact
John Narborough at The Orchard,
Rocks Lane, High Hurstwood,
Uckfleld, Sussex, TN22 4BN.
John's 'mystery' receiver (above).
Below is John's collection of
vintage apparatus.
'Vintage
Ln!
INFORMATION WANTED
... Circuit diagram or the Works
Publication WP 137 (mentioned
on label giving valve details) of a
Burndept Screened Portable.
Valves are PM1HF, PM1A, PM12
and PM252. The set requires a
2V accumulator, 108V HT with
66V tapping and 18V (tapped
every 1.5V) grid battery.--John
Hein, 13 Blane Avenue; Blanefield, via Glasgow, G63 9HU.
Practical Wireless, May 1976
37
Early morning maths
While thumbing through my
husband's PW (February), I
noticed the Editors comments on
digital watches. We have had a
digital clock for over a year now,
and although I can cope with the
24 hour system on it, I am still
sometimes frustrated by having
to mentally subtract numbers
from 60 to find out how long it is
to the next 'o'clock'.
My suggestion (I know nothing
about the electronic practicability
of it) is that we return to the 12
hour system, and that the display
reads the minutes first, with `to'
or `past' in the middle, i.e. 27
past 7 or 29 to 8. This would
abolish the need for mental
arithmetic early in the morning
as the time to get up approaches!
Mrs F R Tasker (Hardwicke)
PS. What happened to the crossword?
fitted
permits -Ed.
This
is
in
when
space
Crystal
controlled pendulum
Your editorial in the February
of
Practical Wireless
issue
caused me a little quiet amusement.
As a retired airline captain, I
am used to learning to accept
new instrument faces, hence the
digital presentation causes me no
pain. However, this does not
deafen me to the complaints of
the female side of my family
ever since I constructed a digital
clock. I am sure that quite a lot
of people have to make a distinct
effort to convert mere numbers
38
to a more conventional mental
picture of time.
A few months ago, I wrote to
another journal making such a
point and asking if they would
publish a circuit which would
marry the accuracy of a crystal
timer to a balance wheel or
pendulum clock. This could be
achieved by comparison perhaps,
plus suitable correcting impulses.
I said I was sure that this would
please hobbyists and horologists
not to mention their womenfolk!
The editor did not agree, hence
my amusement.
You, of course, refer only to
wrist watches. In this case could
not a miniature stepping motor
drive conventional hands, as
employed, I believe, in certain
makes of watch ? -E Rodley
(Guildford).
IC DEW
Is it not time to revisit the
subject of the Digital frequency
meter?
Surely, amongst the readership
of PW there is someone capable
of contributing a device of sound
economic sense, from the vast
array of ICs now available?
B A Martin (Solihull)
We hope to be satisfying people,
such as Mr Martin, very shortly
-
-Ed.
Heavy duty charge
As a reader of PW for many
years and also a keen motorist
(DIY), I submit a humble request
for an article on a battery
charger, something a little more
sophisticated than the straight
forward trickle charger. I would
suggest a charging rate from
about 2A to 8A (for rapid charge),
and using full wave rectification.
Suitable also for 6V or 12V
batteries. I'm sure one could be
built much cheaper than a commercially bought one. -C. Law
(Blackburn)
(Potential
contributors -please
note)
The price of stock
Reading Mr B. A. Pearson's
letter of complaint re transistor
prices in the March issue, stirs me
from my customary lethargy (and
it takes a lot to do that) and
prompts me to put another view
which may not be popular with
all your readers.
In the first place, the correct
price for an 0071 of reputable
make should have been 74p plus
VAT. In the second place the
dealer should be thanked for
keeping this type of transistor in
stock, bearing in mind the fact
that these are not exactly the
most sought -after transistors and
in any case can be obtained in
bulk at give away prices as
seconds or surplus which the
average dealer would not care to
keep or sell.
The third item is this. The
average man in the street knows
nothing of the pitfalls involved
in running a business (be it small
or large). He knows he needs an
OC71 and for convenience pops
into his local dealer trusting that
he will have some in stock. It
could have been any one of
hundreds of different types held
in stock against the time they
are needed (if they are) together
with hundreds of valves, resistors,
capacitors etc. Who pays for the
stock which just lies there as a
convenience? There is no way of
knowing what will be asked for.
If Mr Pearson thinks it is so
lucrative I suggest he draws up
an imaginary stock list, pays for
it all (mentally that is, I doubt if
he would be so bold as to do it)
and then tries to sell it at 25p
per go, that is if he has thought
to stock the item required. -Les
Lawry-Johns (Gravesend, Kent)
Very puzzling
I have taken PW for some
years now, and whenever possible
attempt to complete the `Technicross' puzzle. However, after
many frustrating months, I feel
that it would be beneficial to
those taking part if the answers
were published in the same issue
as the puzzle. Waiting a month
for the correct answers tends to
lessen the enjoyment of the
game.
Perhaps I may also suggest,
that on the whole, the questions
are a little obscure for the
general readership of PW, includ-
ing myself! Am I just a little
thick or is this a generally held
thought amongst the readership?
-A W Bunting (Kent)
We would be pleased to hear
from other readers about their
views on this feature.
Practical Wireless, May 1976
& MAZDA VALVES
All individually boxed
EXPRESS
NEW MULLARD
guaranteed. Full
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fide companies. Price
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and
POSTAGE
12p for
1
Valve.
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DY802
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EB91
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EC/36
EC88
EC90
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ECC81
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ECC83
ECC84
ECC86
EtXì88
ECC189
ECF80
ECF82
ECF86
ECH81
ECH83
ECH84
ECL80
ECL82
ECL83
ECL88
0 69
053
063
116
0-78
0-89
0-e8
0-66
0-60
0-82
016
0-94
0-69
0-64
0-68
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0.78
1-06
077
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0-90
0.76
160
1-06
1-80
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0-72
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EF80
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160
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106
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066
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0.68
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1.87
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1-30
1.80
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PCF808 0.78
PCH200 1.80
PCL82
0-63
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0.78
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089
PCL85
0-72
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0-78
PCL805/860-78
PD600
211
PFL200
PL38
PI.81
PL81A
PL82
PL83
PL84
PL600
0-91
1-06
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1-50
0-78
1-02
NEW VALVES
Individually boxed and
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greatly reduced prices.
Quotations for
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1
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CL33
1-40
CY31
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DK98
DL92
DL94
DL96
DY86
DY87
DY802
EABC80
EAF42
EB91
EBC33
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EBC81
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EBF83
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EBL31
ECC81
ECC82
ECC83
ECC84
EGC86
ECC88
ECH36
BCH42
ECH81
ECH83
ECL80
1
00
00
1d0
100
040
0.00
1/6
0-40
080
0-60
1-00
076
0-60
0-48
066
0-46
0-46
0-47
Oßb
0-70
0-80
1-00
0-76
040
0-40
0-40
0-81
8-00
0-46
0-88
088
0-86
0-46
0-60
1-60
086
086
0-60
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0-41
ECL83
0-76
ECL86
0-66
ECLL800 8-60
EC1A2
EF37A
EF39
EF80
EF86
EF86
EF89
1.60
N79
0-86
0-46
0-60
EF91
EPOS
0-40
OB2
PC86
PC88
PC97
PC900
PCCO4
PCC88
PCC89
PCC189
EF96
EF98
lßd 042
Oß6
060
046
0 80
EF183
EF1B4
0-40
0-40
0-80
EL33
EL94
EL38
EL37
EL41
EL42
EL84
ELM
8 00
166
086
000
PCF80
PCF82
PCF86
PCF801
PCF802
PCF806
PCF806
PCF808
PCL82
PCL89
EM80
EMBI
EM84
EM86
EM87
0-66
0-00
PCL84
PULSO
1-00
1-00
0-46
PCL806/85
ELM
EY61
EY86
EZ40
EZ41
EZ80
EZ81
0Y601
0230
0Z32
0234
HN309
KT61
0-70
0-60
8-40
0 00
Oi0 PCL86
060
0-60
0-76
0.80
0 81
0-00
0-66
0-66
0-76
1-60
3-00
8'40
KT81(7C5)2 00
KT81
1-75
KT88
8-66
KTW81 1-60
KTOB
MU14
1.00
PD600
PEN48
PL98
PL81
PL82
PL09
PL84
PL500
PL604
PL608
PL509
PL802
PX26
PY33
PY81
PYB'1
PY83
PY88
000
0-46
0-46
066
0-66
0-66
0-66
0-46
PL5o4
P1.508
PL509
PL802
PY33
PY81/800
PY82
PY88
PY600A
PY800
PY801
U26
U191
U193
IJAH080
UBC81
0 60
0-60
0-60
0-60
1-60
Oßß
0-68
0.66
060
UCC86
UCH81
UCL82
UCL83
IIL84
UY85
060
0-46
0-60
0-68
0.54
1.22
1-17
0-66
1-01
0-80
1-80
0-78
0-78
1-06
0-73
068
PY600
1-10
PY81/800 0-60
PY801
Od6
BP41
8161
T41
U14
U'26
U28
U191
UABC80
UAF42
U RC41
UBC81
UBF80
UBF89
111.41
UL84
3B4
9va
6R4OY
ßU40
6U4OB
6Y9GT
6Z4G
ó/30L2
BAKE
BAM6
BAQ6
6Á87G
SATO
OAU6
6846
613E6
BBB6
6BW6
6BW7
1
30FLI/
36
PCE8000ß8
30FL2
1-02
30FL12
1-44
30FL14 1-20
30L1/PCC84
0-63
30L15/
PCC805 186
30L17
30P4ME
30P1Z/
PC801
30P19/
PC802
30PL1/
PCL801
30PL13/
PCL800
30PL14/
PCL88
1-12
1-68
1-47
Bc106
0.86
080
066
080
086
046
0-46
BKOM
070
6 %26
1-00
1-25
68L7GT
060
040
0-60
0-66
0-66
0-76
6114
0
046
0-40
706
7B7
708
7Cß
046 7H7
050 7R7
4
0
46
0 66
080
080
2 00
1
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Oß0
0-80
787
7Y4
12AT6
12AT7
12AU6
11/
066
124E7
12846
0-11
0-60
0-96
0-90
0-40
2-00
12BE6
3001
30015
80017
0.40
0.40
0-60
045
1ß0
1-86
0-70
000
100
060
0-40
0-u
0-46
076
0-76
0-66
120
1-40
1-00
1-00
Oi0
6CW4
1-60
2-80
8-00
61,25
OF28
1-00
0-76
090
124U7
SOCIO
30E5
80FL1
80FL2
30FL14
30L1ß
30L17
30P4MR
30P12
30P19
80PL1
e0PLI3
30PL14
3ßW4
315240T
60CD60
807
0-48
0-14
0-18
0-18
1-72
BC10O
BC113
BC117
B011B
4004
080
060
088
0.60
0.40
1.00
1.00
0.00
1.00
1-00
100
1.00
0.96
Oß6
160
100
Oß6
0-96
1.10
1.10
0.60
0.70
1.80
100
813ITT 17-60
813U80R 7-00
8664
2.00
010
016
Oßl
O10
810
BC148
0-08
BCIODC
BC1e2
BOlO2L
B0184L
BC338
BOY82
BOY11
BOY14
BOY70
BOY71
BCY72
BCZ11
BD121
8817400
887401
BN7402
8817403
8E7404
BN7406
BN7408
8877407
8877408
13E7400
8817410
8107411
8107412
8817413
8N7416
8817417
8N7420
8877422
BN7423
0-65
0-48
BF197
BF200
BF861
BF898
BFW10
BFX29
8E188
2-u BFY60
044
oU
OJO
6Q7M
044
086
BC107
BJ60
OLBGC
0-44
1-85
1-08
Bc147
ßL60
060
076
2-u
o66
046
OK7M
BKGG
0 76
A8Y28
BA102
BA116
ßJ551
6K70
BD131
010 BD132
061 8E115
086 BF167
086 8E173
016 8E179
026 BF180
081 BF181
080 8E194
0 85 8E195
0-88
1144
6J7M
OKBOT
BD124
0.1E
0 44
SOIL!!
0J70
0-07
AFOSO
0 60
0-60
0-66
AA119
AAZI3
AAZ16
AC107
AC126
AC127
AC128
ACI76
AC187
AC188
ACY21
ACY39
AD140
AD149
AD161
AD162
AF116
AF116
AF117
AF186
ABY27
1-22
6 VOGT
OCHO
6123
PCF806 1-29
30F5/PF818
0 70
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6CD60
30CR8/
060 6X6(3
016 OXSGT
1*F89
186
1T4
30015/
PCF800 1-22
30017
1-29
016
018
0-11
0-18
016
086
016
046
BFY61
BFY62
BRI00
BY100
BY126
060
0-20
Oß6
Oß8
0-98
0-86
0-86
0-10
0-18
0-16
0-80
Oß0
0-40
0.27
0-14
BYI27
0-12
BZXe1 aeriee
080
BZYBB series
CR81-O6
CR81-40
CR83-06
CR83-40
MJE340
MJE870
MJE620
010
086
0-60
0-40
0 66
0-47
0-68
0-66
11.712965 1-27
MJE8066 0-76
MPFI02 0-40
MPF101 0-86
080
086
0-16
OAIO
040
040
1-00
OA81
0-18
O48
0-16
0-16
0-16
8N7428
8N7430
BN7433
8N7437
0-40
0.18
0-8E
045
2-u 0A79
0ß6
088
042
048
887438
8817440
8817442
0-16
887451
098
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s
0
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086
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0-16
0-25
0-87
1-00
0-72
087
0-87
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8817441 AN
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BN7460
13N7463
1017464
8N7460
8817470
8817473
BN7474
8N7480
BN7483
0-98
0-79
0-16
0-16
0-16
0-16
0-16
086
0-41
To be added
to all orders
25%
INTEGRATED
CIRCUITS 8%
0C45
0071
0072
0076
0077
0081
OC81 D
OC81 Z
0083
OC140
OC170
OC171
OC200
00201
OC202
00203
OCP71
0-07
2TX600
ZTX601
ZTX503
1 00
ZTX631
2-00 ZTX660
0-01
0-06
1-25
040
1-00
0-76
0-60
0-40
O-B0
0-80
0-86
O-u
0-80
0-66
089
088
046
0-60
1-14
0-80
069
0-76
1-60
1-60
076
1
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1N914
IN4001
IN4002
IN4003
184004
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I N4006
I
IN4007
1N4009
1N4140
18921
I82038
1820611
I821001
188010
2N606
281697
281706
287064
2N1181
2N1132
281301
281808
2101804
1811305
0-18
0-15
0-16
0-25
0-18
2N2904
2N2906
9
0-06
0-07
2121053
8-18
9-18
0-10
0.18
2101614
2108616
2141702
0-18
0-06
2N8706
018
2103704
0-07
8-10
0-20
0-10
2108701
2101707
0-14
0-16
0-11
0-16
21i0711
0-20
0-16
0-81
2N290OA 0-86
2N2904A
2N2906
006 2102026
0.08
0.01
2E3065
2E3626
00e 2N9706
212670/
2103709
6-u 286710
046
0-10
/-11
0u
084
041
0-18
O-u
2108610
8N1820
2N6e28
2108908
2N6004
2128906
2103904
2104000
2124069
2124060
1124041
0-66
2N180e
0a
2-a
2811300
8-89
2N4062
0.00
2E1108
1-60
0-20
0-11
0-10
2N42B9
3N186
614141
ZTI801
2E1302
218304
0-14
0-18
0-84
ORP12
ORP60
TIC44
TIC226D
TIL209
ZTX 107
ZTX300
060
089
018
8N7480
0-47
8N7490
0-66
BN7491AN
1-00
8N7492
0-70
8817493 0.70
8817494 0-80
BN7495
0-80
8817406 0-96
8N7497
8-87
88174100 1-89
88174107 0-46
88174110 0-68
81074118
0-90
88174121
0-50
0-70
1-00
0-90
8874119
048 81074122
0-60 8N74123
110 8N74141
VAT
VALVES &
TRANSISTORS
0.391
01200
04201
0016
0020
0ß8 0023
O-u 0025
Oß6 0018
0ü 0036
0ß8 0036
084 0042
Oß0 0044
MPF104
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8-18
new and branded.
Manufactured
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Quantity discounts on
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are
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Valve
0$0 68N70T
Oß0 08Q70T 040
0-60 6UIO
1-60
Oi0 6166
040
UCR42
UCH81
UCL82
UCL83
UF41
UY41
8-00
0-86
1-50
0-76
1-00
0-86
0-76
0-40
0-76
0-60
0-60
0.60
0.110
UCC86
RST
Practical Wireless, May 1976
0-63
1-15
0-56
30C1/PCF80
61187
66
8-00
8-50
0-68
068
070
1-18
OP86
1
0-73
ECC8041ß0
8F23/EF812
Oß6
Oß0
203
8/30L2/
6BJ8
68Q7Á
6BR7
0-60
0-60
1-02
1-80
1.77
066
066
118E89
0.68 UY86
0-66 VR106/30
0-66 VR160/30
0-40 1R6
0-41
0-66
0-00
0-66
0-90
0-80
1-00
0-46
0-70
All transistors, l.C's offered
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application.
DM70
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TRANSISTORS -INTEGRATED CIRCUITS
ld8
281607
281809
281018
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2102147
0-p
9-u
0.46
282160
0-78
0-78
2102048
0-60
8N74145
8N74160
1-86
1-76
1-00
8-00
1-00
1-00
0.96
8-68
1-57
2N2369A 016
ON74161
88174164
BN74166
BN74168
BN74157
82174170
88174174
88774176
88174176
81474190
88174191
40660
40361
40362
40430
p
OP46
0 91
1.86
0-66
0.11
018
0-07
0-15
0-11
1-11
018
0.69
0.60
/-1f
8.10
/-u
Iu
5.14
/.10
818
018
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9J0
1-76
e81
048
/.46
040
016
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8-00
0E74193 1-00
8N74194 140
88174196
8N74196
8N74107
13N74198
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180
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2-77
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110
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200
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14
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tecknowledgey in consumer ICs - and their applications.
SGS Audio ICs
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To accomodate expanded
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t
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5
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The much heralded TDA2020 is here. And just
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Prices
IC
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TBA81OAS
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Larsholt tunerset accesory unit, with pilot tone filter
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aOí t
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£1.75 (kill
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Controls. kit E5.78
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Comp /ere FM Tuner kits, inc case, for use with the above
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7252
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1
}
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homing) £250. P.P.
11
}
L6-90..
J
UNISELECTOR
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U -DEC B
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BARGAIN PACK
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l
T -DEC £3.60.
111
8.4
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AND T -DECS
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£24.00
;z 4e Rio f0
PRI. 240v sec. 27/0/27v at 800 m /a, £2.25. P.P. 50p.
PRI. 110/240v sec. 50v a110 amps, £1000. P.P. E1-50.
PRI. 110/240v sec. 20/21/22v at 8 amp, £6N. P.P. LI '50.
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PRI. 110/240v sec. 24/40v at 1+ amp, L1- N. P.P. 50p.
PRI. 240v sec. 20/40/60v at 2 amp, £3.00. P.P. 70p.
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Dim.
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MAINS TRANSFORMERS
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Amongst our various accessories for entertainment
electronics is a range of FM tuning, frequency and
sig. strength meters with 12v, 50mA bulb. £2.50 ea.
Our R &D facilities are available for
general consultancy to OEMs: Wither
details on application Standard protect
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n
comment data is E15.00 payable in
32p
2A/45v 27p
30p
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25 high street,
essex. em14 4rh.
R
facilities, AMBIT has moved sales
and administration to 25 High St.
Brentwood- The existing 37 High
Street premises are retained for the
engineering activities.
One of the first products of this
move has been the development of
a TV sound tuner, from an "off
air" system, using its own varicap
UHF TV tuner, with ICIF amplifiers and block filters by TOKOAnd then one of our best ever
circuits - an electronic touch tuner,
with scanning mode, and facilities
for 6 preset stations. The unit is
suitable for use with FM, and now
AM of course, and offers a cornplate tuner system without any
I
_
'
Modules & Kits
Nave moved
-4,
-
COMPONENTS1°
Practical Wireless, May 1976
GI NE1tAI4 SERVICING
An occasional series by LES LAWRY-JOHNS
chatting this time on
3 -VALVE RADIOS
radios are still great favourites with
many people. The main reason is economy,
as a mains operated transistorised set large
enough to provide the same bass response tends to
be expensive whilst battery operated sets are either
too small to sound good or are too expensive to
run, bearing in mind the fact that a PP9 battery,
for example, is now over 50p. In addition to this,
some people have a sentimental attachment to their
valve radios. We are quite fond of an old couple in
their nineties, who have a 1933 Ultra! We will not
go into the servicing of this type of set, however!
Suffice to say that we have kept it going for them for
more years than we care to mention.
VALVED
higher the total voltage of the valve heaters the
lower the value of the dropper. This is why nearly
all European radios of this type used 100mA valves
of the "U" series (UY85, ÚL84, UCL82 etc.). Countries with a low mains voltage (say the US) of about
110V used a different range of valves taking more
current and dropping less voltage. Some years ago
it was quite common to find a series chain of 0.3A
valves (25Z4, 25L6 etc.), or a 0.2A chain (CY31,
CL33 etc.), a 0.15A chain or even a 0.16A would
you believe! Also a 0.1A chain which is the most
likely line -up to be found in sets of more recent
HT+
origin.
V5(±-
R1
Transformerless
Valved radios generally fall into two types, the
heavier type having a mains transformer and
parallel-fed valve heaters and the lighter ones with
no transformer and series heaters. The latter is more
commonly encountered and we will consider this
type first.
With no transformer to provide low voltage supplies, the normal 240V mains has to be adapted to
provide the HT and heater requirements. If we
accept that one of the mains supply leads, preferably
the neutral, can be connected directly to the chassis
or metalwork, the design can be simplified so that
all that is necessary is a means of reducing the mains
voltage to that required by the total number of
valve heaters in series. This is usually done by
inserting a wirewound resistor in the top end of the
series chain to drop the voltage to that required. A
tapping on this resistor can be used to supply the HT
rectifier, which is usually a valve, and the current
drawn by the HT must be added to that drawn by
the valve heaters when calculating the value of the
dropping resistor. The arrangement is shown in
Fig. 1 except that a dial lamp and shunt resistor
have been inserted into the chassis return to neutral
(or one side of the mains at any rate).
The advantage of using a valve rectifier is twofold.
First, the valve warms up slowly with the rest and
therefore the HT builds up slowly as the rest begin
to draw current. Therefore the HT is rarely more
than, say, 200V. This takes the strain off all the
capacitors on the HT line and leads to greater
reliability. Secondly, the voltage drop across the
rectifier heater in addition to that of the other valves
reduces the rating of the dropper so that the heat
concentration is reduced in this area. Obviously the
Practical Wireless, May 1976
200-225V
226-250V
04
V5
V4
V7
V2
V1
V6
V3
=03
L,
YN
AC /DC mains
Fig.
1
In AC /DC receivers the heater chain and HT supply were generally of this type.
The number of valves used could vary but the
minimum was usually four including the rectifier,
this line-up being, for example, UCH81 frequency
changer, UBF89 IF amp, detector and AGC, UCL82
audio amplifier and output, and a UY85 rectifier. A
variation on this theme was a UCH8I as above with
another UCH81 as an IF amplifier and audio amplifier with a UL84 output, using two crystal diodes for
detection and AGC. The one advantage with this
system was the possibility of changing over the two
UCH8is if the one in the FC stage was reluctant
to oscillate (which is something they often did, or
didn't!).
The main disadvantage of series -heated valves is
41
the fact that rectifier and output valves are well up
the live mains end with only the dropper and perhaps the dial lamps (some designs) at a higher
potential. This means that there is increased stress
between the heater and the cathode of the valve
with the consequent risk of breakdown, and induced
hum in the case of the output valve. It comes as no
surprise therefore to find the fault of "no valves
glowing" is often due to the heater of the rectifier
being open circuit. It is not that the heater just
feels like failing, it is most often blown due to the
failure of insulation, the high potential AC on the
heater suddenly finding itself provided with a short
cut via the main electrolytic capacitor and chassis.
The rectifier heater is thus treated to an extremely
gay life of somewhat short duration. If there are
dial lamps in the way, these will probably fail also.
A similar short in the output valve may or may not
blow the heaters, only cause them (rectifier and output only) to glow brightly.
Common faults
Now let us consider a few of the more common
complaints and their cures. One of the most common
is hum. Tackling this in a set with series heated
valves is a little different from a set with parallel
heaters. In the latter case one tends to reach for
an electrolytic capacitor of adequate voltage rating,
usually 350V or more, and connect this across the
HT line in one of two places, reservoir section to
chassis or smoothing section to chassis, to see which
section is at fault. The series heated chain does add
the probability of heater -cathode leakage so that
although the test electrolytic capacitor can still be
tried, one is not surprised if there is no difference.
The next step is to see if the hum continues with
the volume turned down. If it does, it is reasonable
to suspect that the output valve (probably a ÚL84
or UCL82) has heater -cathode leakage or is drawing
grid current, the net result being the same. So
change the valve.
If the receiver uses a printed panel, there is the
added possibility of leakage across the surface of the
panel or through it. The affected area will usually
/'
,=
Jí
-set
manufacturers often seem more concerned with appearances-
be blackened and a little cutting away of the plastic,
perhaps combined with replacing the affected tracks
with wire, may have to be resorted to. Set manufacturers seem often more concerned with appearance
than efficiency and mount resistors close up to the
panel with the leads cut short. Replacements should
be made with longer leads so that the resistors stand
well up off the panel, however ugly this may appear.
Resistors, like politicians, should be open and
above board!
'
Do not omit to check the grid resistor of the output
valve which sometimes goes high particularly if the
valve has been drawing grid current. A grid leak
resistor of say 1M;í2 or 470kí2 can often rise to many
megohms leaving the grid floating and humming
away to itself. Quite often the hum varies with the
volume control setting and this means we have to
look back to the preceding stages. Usually either the
IF amplifier, say UF89, or the frequency changer
(UCH81) is at fault and the latter, being more
expensive of course, is usually the culprit!
....
m
/
F¡i
i
No results
:D
o
,.
:/its;
*
/. 1r /, //'/ ,I,10'0 /
ih0iiíi
/ j
::::iioe
f'!n,//
/í 7jr....::Iu`i' _ ;,
%.`_Yi',
1011010
%
,'
`%
%
'
.
(
%e0
I
i'
:,
;
.4*.,
-one common complaint
42
is
/P'','
hum-
ÿ%/4 ,
.
One of the most common complaints is that the
valves light up but there is precious little other
activity. The usual reason is that the smoothing
resistor has failed but one must not assume this. The
output transformer could have an open circuit
primary or there may be no supply to the rectifier
due to an open circuit surge resistor (Rl in Fig. 1),
perhaps little Johnny has moved or unscrewed the
internal loudspeaker muting devices on the external
speaker panel (you did it, but blame Johnny anyway).
So we must proceed logically. If there is a fine
upstanding dropper it is no trouble to check all
sections with a neon when the set is on or an
ohmmeter when the set is off (if you're too lazy to
switch the meter to the AC range and check the
voltages on the dropper tags with the set on). Many
sets did not use a single dropper however and the
surge limiter may be a separate wirewound resistor
Practical Wireless, May 1976
mounted in a more inaccessible position. If the value
cannot be read it can be assumed to be in the region
of 100(1. If a printed panel is used, the resistor may
be intact but it could have parted company with its
print beneath.
Assuming the rectifier is receiving its supply however, there should be HT on at least one of the main
electrolytic capacitor tags. If there is a good voltage
on one but not the other the smoothing resistor (or
choke if it's an older set) could well be open circuit.
The value of this will depend upon whether it has to
pass the total HT current. Quite often, the output
transformer primary is directly connected to the
rectifier and therefore the anode current of the output valve does not pass through the smoothing
resistor. In this case the value may be quite high,
say about 3kfl. If the voltages are ok at both the
smoothing tags, check the voltage at the anode of
the output valve. If output transformers have a bad
habit it is that they go open circuit on the winding
which feeds the anode! This means a new transformer. If an exact replacement is not to hand an
alternative can be used, the important thing being
that the correct impedance matching is maintained.
Very generally speaking, a small battery output
valve requires a high impedance, the normal type
of valve encountered in mains operated sets a
medium impedance, whilst a low impedance is only
required for more high powered amplifier type
valves (and output triodes if you can remember that
far back).
-a hefty charge which
can tickle you
pink-
Don't forget that if there is no discharge path
through the HT line, the reservoir capacitor can be
left with a hefty charge which can tickle you pink
if you let it! The capacity is not that used in TV
receivers (about 100 to 300µF) which can really cause
a spark but even a 32µF on a 300V line can pack a
punch which is not to be sneezed at!
The Thorn group made a large number of models
with the "U" series of valves on a printed panel
where not only the smoothing resistor had a habit
Practical Wireless, May 1976
of becoming O/C but also parted company with its
print, as did the surge resistor to the ÚY85 anode.
These were fairly small wirewound resistors and
serve as an illustration of what we have been going
on about in the above text.
The audio amplifier
Having checked the HT supply and output stage,
and ensured the latter is operating under the correct
conditions, with the cathode bias components in order
(resistor the right value and the capacitor doing its
job) check the output grid to ensure there is no positive reading. If there is such a reading, the valve
could be drawing grid current, highly likely, or the
coupling capacitor from the audio amplifier anode
could be leaking, less likely but still a strong possibility. We then turn to the preceding stage Which
is normally either a separate triode section in the output valve or the triode section in a valve like a
UABC80 (three diodes and a triode in one envelope).
The only component likely to require attention is the
anode load resistor which is normally about 220k11.
This does tend to "go high" producing loss of volume
and a peculiar form of distortion (stressing the sibilants, you could say). This is no trouble as the voltage
at the anode will be very low and this itself suggests
the resistor is the primary subject.
A low voltage need not be due to the resistor and
if this proves to be of correct value, attention should
be directed to the control grid. This is normally
biased by a high value resistor of up to 10M(1. If the
coupling capacitor (the charge on this determines the
bias with the resistor) is leaky, the bias is cancelled
and the valve draws too much current. The voltage
drop across the anode load is therefore excessive and
is responsible for the condition. Some receivers do
use cathode bias, and where this is so the cathode
capacitor could be shorted, or the grid coupler could
still be leaky, but most receivers have the cathode
directly coupled to chassis as this simplifies the
design.
Most sets have the volume control feeding the control grid and if the coupling capacitor is leaky the
position of the control will vary the distortion to an
extent. Which of course brings us to the vexed subject of noisy controls. Usually a squirt of cleaning
fluid into a convenient gap in the housing will bring
the control to heel but it is sometimes difficult to find
or make a gap. The construction of the control either
makes this operation very easy or very difficult and
it is sometimes necessary to partially strip it or replace it completely. The control itself is not always
responsible however and associated capacitors should
be checked for leakage as control tracks do not take
kindly to the passage of DC current. This is particu
laxly so in the case of some makes of unit audios
and radiograms of more recent origin but since these
are transistorised this thorny subject will not be pursued further.
The IF stage
The detector and AGC circuitry in valved receivers
very rarely gives trouble so we may be forgiven for
nipping smartly past these and delving into the IF
stage. Once again this can be quite simple, with the
cathode chassis connected and the control grid biased
from the AGC line. Note that valves are always reversed biased, i.e. the control voltage pushing the
43
valve toward cut -off and is therefore negative -going.
The HT supply to the anode and screen is via a decoupling resistor of some lki2 with a capacitor to
chassis of from 0.047 to 0.1/4F. This decoupling point
can be the screen pin of the valve base with a short
lead to the IF transformer primary, or to the latter
point with a short connection to the screen pin.
Separate supplies are often used so that the screen
grid of the IF amplifier can be connected to the same
electrode on the frequency changer base and two
resistors are often used as a potentiometer to hold
the screens steady, typical values being say 22k52
from HT to the valve base with a 47k.í2 to chassis.
As the majority of the current passes through the
upper resistor, 22k52, this is often the one to change
value and thus drop the applied voltage. This is
sometimes the cause of the complaint, "My radio
has been getting weaker and weaker and now you
can hardly hear it ".
Instability is another common disorder and this can
vary from whistles and screeches to non-operation
due to the paralysing effect of the AGC being overloaded by the instability. This can be a trifle tedious
to overcome and the normal remedies are not always
effective. The usual first step is to try bridging the
decoupling capacitors with a test 0.05µF or similar.
Bridging from screen to chassis may stop all complaints right away and you then go on your way
rejoicing. But more extensive checking around may
have to be resorted to, bridging other capacitors
associated with the IF and frequency changer stages,
the AGC line and the HT line. If none of these efforts
produce results, check the alignment of the IF transformers, the valves, earth contacts (especially if these
are riveted) and the main electrolytics.
Frequency changer stage
For AM reception this is usually a conventional
triode heptode such as a UCH81. The complaint of no
normal reception with, perhaps, some background
mush is often the result of the valve becoming defective and refusing to oscillate (triode section). When it
is oscillating there should be a negative voltage on
the triode grid. If this is absent a new valve will
usually put things right. If it doesn't, a general check
up on the capacitors and resistors, comparatively few
in number, associated with the section will usually
restore signals. A defective coil is sometimes difficult
to locate if it is suffering from shorted turns but with
a bit of luck the trouble may be the result of a badly
soldered lead -out or even an open circuited lead -out
which can be repaired.
The mixer section is similarly wired to thé IF
amplifier and the same remarks apply regarding
resistors changing value, leaky decoupling capacitors
and the like. It varies in the arrangement of the
control grid which is blocked from the aerial coils as
a rule with a fairly low value capacitor, say 100pF,
and with a fairly high value resistor connecting to
the AGC line.
The aerial circuit may consist of a ferrite rod on
which is mounted the tuning coils with leads to the
tuning gang, the wavechange switch and chassis, but
there are infinite variations on this theme. If there is
no ferrite rod (the design is older) there is usually a
cluster of coils around the wavechange switch and an
open circuit on one may result in the others being
put out of action. They are probably slug tuned for
padding with separate trimmers for lining up the
high frequency end of the scale. Where ferrite rods
44
are fitted the actual rod is the slug and the position
of the coils on the rod is varied for padding on the
low frequency end of the scale.
VHF -FM
Receivers with these facilities have a separate
section due to the higher frequencies involved. The
aerial input can conveniently be a half -wave dipole
made simply by opening up a piece of twin flex to
the required length and stapling this in the cabinet.
This is all very well in some areas but if serious
listening is demanded a more elaborate system is
needed with the correctly matched down lead, 7552
coaxial on most UK stuff, 30012 balanced twin on
imported, as a rule. We will not go into the pros and
cons of these different inputs here as they are pretty
well known and have been discussed at length in
previous issues.
The aerial input is taken to the tuning coils and
thence to the first section of a double triode, as a
rule, say a UCC85. The second half functions as an
oscillator. Nine times out of ten replacement of this
valve will restore normal signals if these fail suddenly, the tenth time being the result of defective
resistors or capacitors. The actual tuning may be
carried out by separate sections on the gang capacitor or by varying the position of the slugs in the
aerial and oscillator coils. The output of this usually
small section is fed to the IF stages, there may be
more than one, through separate transformers to a
ratio detector. The two diodes involved in this latter
operation may be in a valve envelope (as in the
UABC80 for example) or separate germanium or
silicon diodes if the valve line -up does not include
such a valve.
HT+
All
heaters
ti
Mains
wieg
Fig. 2. AC -only sets have the conventional mains trans former with the
valve heaters in parallel.
AC -only
sets
The advantage of using a mains transformer is that
the valve heaters can be wired in parallel (all at the
same low potential) so that the stress between the
cathode and heater is largely removed, and that the
chassis can be isolated from the mains. Note we
said, "can be." Some receivers sacrifice this advantage
Practical Wireless, May 1976
on the grounds of economy. Some transformer supplied sets use a series chain of heaters but this is all
matter of design considerations.
Some pretty weird and wonderful sets were imported some years ago using difficult valves which
did tax one's resources but this is a story of its own
which we may relate on another occasion. The average type of AC mains set which is likely to be encountered and which is probably worth renovating
will have a transformer supplying a full wave rectifier and valves having 6.3V heaters (possibly 5V
for the rectifier heater). The rectifier may have
a
between 250 and 350V applied to its anodes from a
centre tapped winding, the centre tap being chassis
connected. The output of the rectifier is taken to
the reservoir capacitor which may have a value of
between 8 and 32, F. The circuit is then much the
same as that previously described, using a smoothing
resistor, a choke or part of the output transformer
before the smoothing capacitor. The rectifier valve
may be directly heated (cathode is the heater) which
has a very fast warm up or indirectly heated
(separate cathode) which warms up and becomes
operative with the other valves. The latter imposes
less stress on the capacitors, Fig.2.
channel if the instrument is stereo whilst higher
quality grams which are more likely to be worth
saving may have four such valves, two in push -pull
for each channel. The complication arises not only in
the output transformers but in the drive from the
audio stage to the output pair. An output transformer
primary may haire five lead outs, HT to the centre tap,
a tap for each screen (this provides to degree of
feedback) and the outer taps for the anodes.
Valves in push -pull need differing grid drives so
that some form of phase splitter is necessary. A common method is to use a triode suspended midway
between the HT line and chassis with one output
valve driven from the anode and the other from the
cathode (when the anode is positive going, the
cathode is negative thus providing the "I push, you
pull" requirement). This in turn means that the grid
of the triode is returned to cathode at a fairly high
potential. There are so many variations on this theme
that detailed description is impractical, at least in
this article, so that one should not be surprised if
the voltages in the driver stages appear abnormal.
Stereo does at least supply us with a ready made
comparison circuit so that if one side is working well
we know what to expect in the side which isn't. Get
the voltages right and most else falls in line. Where
they are wrong, check the resistors for correct value
and the capacitors for leakage. Then suspect the
,valves.
Mail Order
Protection Scheme
The Publishers of Practical Wireless are members of the
Periodical Publishers Association which has given an undertaking to the Director General of Fair Trading to refund
-old timers
which really need tracking
down-
monies sent by readers in response to mail order advertisements, placed by mail order traders, who fail to supply goods
or refund monies owing to liquidation or bankruptcy. This
arrangement does not apply to any failure to supply goods
advertised in
If a rectifier valve is difficult to obtain and it is
decided to wire a couple of silicon diodes across the
base, this stress must be recognised as the switch-on
surge may be greater than the rating of the capacitors, To avoid this the inclusion of a thermistor between the rectifier output and the reservoir capacitor
will add to the long term reliability of the receiver.
Valves such as the EZ80 and EZ81 are still
generally available and should be used whenever
possible. Older types such as the EZ40 and the like
need a bit more finding but it is the old timers like
the 5Z4 and 5Y3 which really need tracking down
and it is here that the diodes may have to be used.
Little need be said about the other stages. They
follow the lines already discussed but one is more
likely to find different output stages in higher priced
radiograms etc. For example, a cheaper type may
use a single EL84 (or ECL86, for example) for each
Practical Wireless, May 1976
a
catalogue or in
a
direct mail solicitation.
the unhappy event of the failure of a mail order trader
readers are advised to lodge a claim with Practical Wireless
within three months of the date of the appearance of the
advertisement, providing proof of payment. Claims lodged
after this period will be considered at the Publisher's discretion.
In
Since all refunds are made by the maguind voluntarily and at
its own expense, this undertaking enables you to respond to
our mail order advertisers with the fullest confidence.
For the purpose of this scheme, mail order advertising is
defined as-
'Direct response advertisements, display or postal bargains
where cash had to be sent in advance of goods being delivered'.
Classified and catalogue mail order advertising are excluded.
45
ON RECENT DEVELOPMENTS
NOSEY!
Electronic noses have been around
on the Amateur construction scene
ever since suitable sensors became
available. These, however, have
found most use in such applications
as fire/smoke detection etc.
A Watford company has managed
some success with an explosives
detector. It's called the unassuming
name PD2, weighs a mere 221bs and
lives in an innocent -looking suitcase.
The unit gives a positive response
when explosives are detected. An
audible alert sounds immediately
after taking an air sample containing
explosive vapour. The unit is so
sensitive that it is able to detect the
tiniest traces of explosives such as
those which might be found on a
persons hands after handling explosives-or on their clothing. The
photograph shows a security officer
checking a bag. If you want one of
these units the UK price is around
£2,150. Probably not a high price for
something that nose what it's about.
THE `CHIT'
The NRDC (National Research
Development Corporation) has encouraged many good ideas and
another has just found its way into
my hands. It's called CHIT, standing
for CHeap Input Terminal and was
developed at the National Physical
The
46
e
Laboratory. The approach used is
quite ingenious. Two oblong lengths
of resistive material are laid one on
top of the other.
When a point (a pencil) is used to
draw or write on the top oblong, the
pressure causes the air gap between
the two resistive surfaces to decrease
and the two oblongs make contact at
the point of impact. Electrodes are
connected to each of the oblongs at
their ends and when a current is
passed through one of the oblongs, a
uniform voltage gradient is developed
along its entire length. The voltage
at the exact point of contact i.e.:
wherever the pencil tip happens to be
pressing at any given instant in time,
will be proportional to the pencil
point's position on the x axis. The
other oblong is used as a sort of
wiper of a potentiometer and will
attain this voltage. The two oblongs
are switched, electronically, so that
first one oblong is acting as a position
indicator and the other the wiper of a
pot, then the roles are reversed due
to the electronic switching. Thus the
point can be monitored in both x and
y axis.
Using this method as an input
terminal, handwritten characters can
be transmitted, signatures verified,
line drawings, circuits etc can be
transmitted. Perhaps it won't be too
long before you will write a letter on
such a device and it will be transmitted at the same instant and
received immediately. We seem to
/ecuowc sniffer type PD2
have come a long way since the
Penny Black back in 1840. If it comes,
it could mean that many postmen
will be looking for a new post -do
you see?
FLAT TV SCREENS
have made
From time to time
comments about flat screen television "tubes ". Research and development has been going on in this
area for some time and the latest
effort to come to my attention looks
very promising. First, the US Airforce is going to try out the idea
and believe you me the American
military do not waste time on impractical ideas no matter how clever
they might be. The device is the
brainchild of Hughes Aircraft who
have vast expertise in many areas
not the least of which is electronics.
Some 18 months ago Hughes brought
out a lin2 liquid crystal display which
was capable of showing a television
picture. The company successfully
deposited a number of liquid crystal
picture elements on a piece of
silicon which also contained the
excitation circuitry. Manufacturing
defects caused problems but once
these
were
overcome
Hughes
steamed ahead. Now, four on the lin.
miniature "tv screens" have been
butted up together to form a 2 x tin.
display comprising a 100 x 100 cell
array.
It has been rumoured that the US
Airforce has shown great interest in
using the new approach for things
like scan -converted radar, forward looking infrared and possibly in
head -up displays for gun aiming. In
sunlight, it's difficult to see the
cathode ray tube type of display
whereas the LCD component is
reflective and thus thrives in such
conditions. Another distinct advantage is that crts commonly
required high voltages -often thousands of volts. The LCD array
requires only 25V. Plans are already
afoot to produce a larger array and it
is easily technically feasible.
I
-
MORE HOTLINES ON PAGE 57
Practical Wireless, May 1976
is3),vemiazit
INNIXTMONTH'i
PRACTICAL
-
WIRELESS
i
-rho
y
.
DIGITAL FREQUENCY
METER
Start
kHr
INK7
Fr
1s'
I
I
100ms
-_I
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_.I
_I LI I_
DC
MAINS
10m
lms
i>li RESET
MN/
MODE
RANGE
DIGITAL
FREQUENCY
METER
INPUT
On
Cff
dia
You'll probably find that you
have a lot of the components already! An interesting constructional project which will give
much satisfaction when it's completed. Readout to, typically,
27MHz or more depending upon
the IC's used. Gate tines of 100ís
to Is. Input 6OmV to I0V and
time intervals Ims to 9999s.
Talking
Transistors
to know how they work
- getting
E
INtHE
ïcn M THESULM
APRIL
1011
OCEOK FOR
PROCEDURES
r
PR
--TO LOC
SERVICING
-AT
TYPICAL
TIPS
wH
HINTS -_ .............. ..:....
ON SALE IN MAY
.
Practical Wireless, May 1976
47
og
l
4,9
RHYTHM
PART
1
IAM045B)
Tempo
SPECIFICATION
Clock
500mV max Variable
Output to external amplifier
15
Number of rhythms
Number of percussion instruments 9
15 to 100 bars /min.
Tempo (useful range)
Number of elementary times
24 or 32
per rhythm pattern
Number of bars per rhythm pattern 2 or 4
Supply voltages from internal
12V
5V
12V
power supply
LED
Down -beat indication
Foot -switch socket
External stop and reset
4 -bit binary code
Rhythm selection
Foot
generator
switch
socket
stop and
reset
51
Stop
Clod
A-
MORE and
+5v
more people these days are taking
IN8
an interest in making their own music and
to that end electronics is playing an ever increasing part. Witness the number of construc-
IN4
tional articles that have appeared for synthesisers,
organs, electronic pianos, musical boxes, guitars etc.
An essential part of most music is rhythm and what
IN2
N1
Code
CODE
Input 81 Input
1
1
1
1
1
1
1
1
1
1
0
0
0
0
¡
0
0
0
0
4
Snare/
Claves
Input
1
0
0
2
Input
0
1
0
1
1
1
0
0
0
1
0
1
1
1
1
1
0
1
1
0
0
1
0
0
0
0
0
0
0
0
0
0
1
0
1
1
1
1
1
1
1
0
0
2
switches
53
S4
S5
56
16
15
Rese
RHYTHM
1
S
S
S
S
S
S
S
S
S
C
C
C
C
C
C
-
Waltz
Jazz Waltz
Tango
March
Swing
Foxtrot
Slow Rock
Pop Rock
Shuffle
Mambo
Beguine
3/4
3/4
2/4
2/4
4/4
4/4
6/8
4/4
2/4
4/4
Down -beat
114indicator
Down -beat
monostable
LED
4/4
4/4
Cha Cha
4/4
Bajon
4/4
Samba
4/4
Bossa Nova
No selected rhythm
Regulated
power supply
AC mains
unit
E
12V
Fig. 2: Table
48
of Rhythm selection input codes. This table may
out and stuck on the facia of the unit.
be cut
Fig.
1
:
Basic block diagram of the Rhythm Get
Practical Wireless, May 1976
ENERATOR
IASSIMINMONI
A.S.WEBB B.Sc
INSTRUMENTS
Bass
drum
11
(BD)
High
bongo
(HB)
Low
bongo
(LB)
Maracas
(MR)H
13
14
Cl
52AA
rthm
Short
cymbals
(SC)
Long
cymbals
(LC)
Conga
drum
(CD)I--
Snare
drum
(SD)F---
arator
12
S2
S
Select SnarepCL
ves
or Claves
Claves
Tone
CL)
,
Volume
Output
Pre -amplifier
showing the M252AA integrated circuit as the heart of the system.
Practical Wireless, May 1976
better method of turning a solo performance into
a duo than with the addition of a drummer and full
drum kit all contained in a box measuring little
more than 205 x 152 x 102mm (8 x 6 x 4in)! In
addition such a portable unit could well provide the
rhythm section for a small group or a novel gimmick
on the disco scene.
This article describes the construction of a
Rhythm Generator containing nine percussion
instruments which can be programmed to play any
one of fifteen different rhythms. Emphasis has been
placed on simplicity of construction and low cost
without sacrificing the faithful reproduction of the
sound of each instrument. Anyone who has had
some experience of soldering and knows one end of
a diode or electrolytic capacitor from the other,
should, with a little care and patience, be able to
make this unit. Several MOS (Metal Oxide
Semiconductor) integrated circuits are used but for
those who are not familiar with the handling of
this type of device full instructions will be given. In
the meantime do not be tempted to remove them
from the protective conducting foam packing.
Generator block diagram
Fig.1 shows the block diagram for the Rhythm
Generator. The heart of the generator is the
M252AA MOS integrated circuit manufactured by
SGS -ATES. This device incorporates a memory
programmed with fifteen different rhythm patterns
which are selected by a 4-bit binary code. The four
code inputs are designated IN8, IN4, IN2 and INl
each one capable of being switched to `0' (i.e. `0'V,
switch closed) or '1' (i.e. +5V, switch open) by S3,
S4, 55, S6 respectively. Thus 16(2') combinations
are possible, fifteen of which are used to programme
the following rhythms:- Waltz, Jazz Waltz, Tango,
March, Swing, Foxtrot, Slow Rock, Pop Rock,
Shuffle, Mambo, Beguine, Cha Cha, Bajon, Samba
and Bossa Nova. Details of the particular codes are
given in Fig. 2 with code 1 -1 -1-1 having no selected
rhythm.
The chip is driven by a square wave from the
49
IAM04591
3640 bits
Multiplexer
ROM
matrix
8
Output logic
and driver
Instruments
External
reset
Decoder
Clock
1- - - - -15
Rhythms
Phase
-2
generator
divider
5 stage
counter
24 stage
rhythm
detector
Re
et
log
c
-
Dow
Decoder rhythms
O
+
O
4
2
Inputs
Binary code
Fig. 3: Block diagram
of the M252AA Rhythm Generator. Rhythms
are selected by applying either a logic '1' or '0' to the input gates
clock generator, the frequency of which determines
the tempo of the rhythm. Once a code has been
selected the various instruments are triggered in
the correct sequence to provide the particular
rhythm pattern. Only eight of the nine instruments
are used at any one time, the snare drum being
manually selected by S2 for the Waltz, Jazz Waltz,
Tango, March, Swing, Foxtrot, Slow Rock, Pop Rock
and Shuffle whilst the claves are used for the
remaining South American rhythms. The outputs
from the instrument simulators are combined and
fed to a pre-amplifier incorporating volume and
tone controls.
A down -beat indicator in the form of an LED is
included to mark the beginning of each rhythm
pattern. A combined stop and reset facility (S1)
allows the generator to be stopped and restarted at
the beginning of a bar. This feature permits the
rhythm to be brought in on the down -beat after the
introduction to a piece of music has been played. To
make this easier while playing, a socket has been
provided wired in parallel with the stop switch Si
on the panel, so that a foot operated switch may be
connected.
The M252 Rhythm Generator
The internal operation of the M252 IC is shown
in Fig. 3. The clock input is first divided by two and
this output drives a 5 -stage counter which resets
every 32 pulses for rhythms of 4/4 time and after
every 24 pulses for 3/4 time. The counter states are
then decoded to drive the ROM (Read Only
Memory) matrix which has been pre-programmed
with the fifteen different rhythms. The binary code
that has been entered to select a rhythm is decoded
and used to determine the reset point of the counter
and to programme the multiplexer to select that
50
of the IC.
particular rhythm from the output of the memory
matrix This output is then fed to the driver circuit
which modifies the pulses to make them suitable for
triggering the percussion instruments. The output
section also includes logic circuitry to reset the
memory outputs to zero after each reading so that
the output will always be able to provide the
correct trigger edge during the following beat.
The internal reset pulse of the counter is routed
to an output connection (pin 7) which, with the
addition of a blocking diode to separate the signals,
can furnish the down -beat indication as well as
allowing the external resetting of the rhythm.
Clock Generator
The clock generator circuit, see Fig. 4, is a simple
astable multivibrator utilising two 2 -input NAND
gates (IC2b and IC2c) together with the timing
components R3, VR1 and Cl to provide a square
wave output to drive the M252 chip. By closing the
STOP switch (S1) the clock is inhibited with its
output remaining at "1" and at the same time the
M252 is reset via IC2a and Dl. Upon opening the
switch the output immediately goes to '0' thus
generating the first command pulse and the rhythm
commences with the first beat of the bar i.e. the
down-beat.
The frequency of the clock may be continuously
varied from approximately 5Hz to 50Hz by the
tempo control VR1. The relationship between the
clock frequency and the rhythm tempo is given by
the following formula:No. of bars /min =
Clock frequency xNo. of bars per rhythm pattern x60
No. of counts per rhythm x 2
Practical Wireless, May 1976
R1
102a
14 4011A
1414011A
810
12
11
3
4
D1
13
1N914
SK1
{To foot
HB
C18,R`6
LB
C22,R44
R3
100k
y--
cy
R2
Stop,
operated switch)
C14 R28
1C2c
1
3
N
BD
1
IC2b
22k¡>
4011A
1/4
RHYTHM GENERATOR IC WITH BINARY CODE SWITCHES
-e- - +5V
CLOCK GENERATOR
22k
IC1
100n7
Tempo
VR1
M252AA
1M lin.
6
16
4-1
CL
C26,R2
SD
C30,R60
S2
12
CD
LC
15
SC
MR
C2
m10nF
+12V1-
DOWN -BEAT INDICATOR
R9.>
+5V
+54
680>
R4 220k
I.
I038
I03a
,
LED,
'.3 4
l44011A
1i44011A
1g4011A
D2
1C3c
12
22k
1R12
>22k
4>22k
54
55
56
RIO
811
22k
53
R13
1
&
R8
11
39k
2
13
Tr1
C3
ßC108
220nF
SNARE DRUM, LONG CYMBALS, SHORT CYMBALS AND MARACAS.
NC.1
+5V
D3
Tr2
BC108
A1N914
+124
Tr3
BC108
SO
C4
100nF
816
22k
R21
R22
2.2k
1M
D6
010
4.7nF
1N914
:
R17 1M
R27
4<<--ñrk
25Ck,
C5
330nF
013
0
1-
To VR9
and C34
C9
R18 1M
MR
C6
220nF
R20
22k
470k
R19100k
5
134.2.
R14
50nFmrs
D 914
1N914
C8
T100nF
jj
Fig. 4: Part
IDN04601
of the circuit containing the clock generator, downbeat indicator, snare drum, long cymbals, short cymba +s and maracas. These
Practical Wireless, May 1976
particular circuits are all housed cn one PCB.
5
1
The Black Watch kit
£14.95!
* Practical -easily built by
anyone in an evening's
straightforward assembly.
* Complete -right down to
strap and batteries.
*Guaranteed. A correctly assembled watch is
guaranteed for a year. It
works as soon as you put the
batteries in. On a built watch
we guarantee an accuracy
within a second a day -but
building it yourself you may be
able to adjust the trimmer to
achieve an accuracy within a
second a week.
The Black Watch by Sinclair is unique.
Controlled by a quartz crystal, and
powered by two hearing aid
batteries, it uses bright red LEDs to
show hours and minutes, and
minutes and seconds. And it's
styled in the cool prestige Sinclair
fashion: no knobs, no buttons,
no flash.
The Black Watch kit is unique, too.
It's rational - Sinclair have
reduced the separate
VII
'
components to just four -and
it's simple: anybody who can
use a soldering iron can assemble
a Black Watch without difficulty.
From opening the kit to wearing the
watch is a couple of hours' work.
Touch and tell
Press here for hours and minutes...
here for minutes and seconds.
Batteries easily replaced at home.
f(i.
EJ
1
The specialist features of the Black Watch
Smooth, chunky, matt -black case,
with black strap. (Black stainless steel bracelet available as extra see order form.)
52
Large, bright, red display -easily read
at night. Touch -and -see case no unprofessional buttons.
Runs on two hearing -aid batteries
(supplied). Easily re -set using special
button -no expensive jeweller's
service.
Practical Wireless, May 1976
Complete kit
The Black Watch -using the unique
Sinclair- designed state -of-the -art IC.
The chip...
The heart of the Black Watch is a
unique IC designed by Sinclair and
custom-built for them using
state-of- the -art technology integrated injection logic.
This chip of silicon measures only
3 mm x 3 mm and contains over
2000 transistors.The circuit includes
a) reference oscillator
b) divider chain
c) decoder circuits
d) display inhibit circuits
e) display driving circuits.
...and how it works
A crystal -controlled reference is used
a chain of 15 binary dividers
which reduce the frequency from
32,768 Hz to Hz.This accurate
signal is then counted into units of
seconds, minutes, and hours, and on
request the stored information is
processed by the decoders and
display drivers to feed the four
7- segment LED displays. When the
display is not in operation, special
power- saving circuits on the chip
reduce current consumption to only
a few microamps.
to drive
1
The chip is totally designed and
manufactured in the UK, and is
LED display
the first design to incorporate
all circuitry for a digital
watch on a single chip.
£14.95!
The kit contains
1. printec circuit board
2. uniqueSincleir-designed IC
3. encapsulated quartz crystal
4. trimme r
5. capacitor
6. LED display
7. 2-part case with window in
position
8. batteries
9. battery-clip
10. black strap (black stainless steel bracelet optional extra see order form)
11. full ins:ructionsfor tuild ng
and use
All the too s you seed a e
aine
soldering iron and a par of cutters.
If you've any quer es or problems in
building, ri'ig or write to Sinclair
service department fcr -ielp.
Trimmer
Quartz crystal
Batteries
Take advantage of this
no -risks, money -back
offer today!
The Sinclair Black Watch is fully
guaranteed. Return your kit in original
condition within 10 days and we'll
refund your money without question.
All parts are tested and checked
before despatch -and correctly assembled watches are guaranteed
for one year. Simply fill in the FREEPOST
order form and post it- today!
Price In kit form: £14.95 (inc. black
strap, VAT, p & p).
Price in built form: £24.95 (inc. black
strap, VAT, p &p).
2000-transistor silicon integrated circuit
1
To:
Sinclair Radionics Ltd, FREEPOST, St Ives, Huntingdor, Cambs., PE17 4BR.
Please send me
Total£
(qty) Sinclair Black Watch
kit(s) at £14.95 (inc. black
strap,VAT, p &p).
enclose cheque for £
made out to Sinclair RadionicsLtd
and crossed.
(qty) Sinclair Black Watch(es)
built at £24.95 (inc. black
strap, VAT, p &p).
Please debit my Barclaycard/Access/
American Express account number
I
(qty) black stainless -steel
bracelet(s) at £2.00
(inc.VAT, p&p).
Name (please print)
Address
Sinclair
Sinclair Radionics Ltd,
London Road, St Ives,
Huntingdon, Cambs., PE17 4HJ.
Tel: St Ives (0480) 64646.
Reg. no. 699483 England.VAT Reg. no:213817088.
Practical Wireless, May 1976
PW/5
Signature
IFREEPOST-
no stamp required.
Delete as required
53
*
components list
Resistors
R1
22kS2
R2
R3
R4
R5
R6
R7
R8
R9
R10
22kn
100kû
22kn
R11
22kû
22kû
22kû
22kû
10kû
R12
R13
R14
R15
R16
R17
R18
R19
R20
R21
R22
R23
R24
R25
R26
R27
R28
R29
R30
R31
R32
R33
R34
R35
R36
R37
VR1
VR2
VR3
VR4
VR5
VR6
VR2 to
?Oki/
22k12
2.2MS2
3.9ki2
680
22k.û
1Mn
Mû
1
100kû
470kû
22kû
1
Mn
1
Mi2
R41
10kû
R42
R43
R44
R45
R46
R47
R48
R49
R50
68kí2
390kí2
R51
390kû
12kû
47kû
27kû
Mû
4'7kí
4.7k0
1
R61
56kû
12kû
47kn
27kn
150kn
68kû
10kû
R62
R63
R64
R65
R66
R67
R68
R69
R70
68141
R71
100kn
12kû
R72
R73
R74
47ki2
All } watt 5%
1Mn linear
100kû
250kû
500kí
500kí
500kí
9
Tr2
Tr3
Tr4
Tr5
Tr6
Tr7
Cl
150kí2
68kí2
12kû
47kí
150kû
68kû
10kû
68kí2
2N1132 or equivalent
BFY51 or equivalent
M252AA
CD4011 A
CD4011 A
CD4011A
Op Amp
Regulator 12V 100mA TBA 625B
741
D1
1N914
D10
D2
LED 0.2"
D11
D3
D4
D5
D6
D7
D8
D9
150kû
68kû
10kû
68kû
1
BC108B
BC108B
BC108B
BC108B
C2
C3
C4
C5
C6
27kí2
R52
R53
R54
R55
R56
R57
R58
R59
R60
22141
Semiconductors
Tri
BC108B
27kû
R38
R39
R40
Mit
12kû
47kû
27kû
150kû
1
014 (
D15J
D16
D17
D18
PIV 1A
5V6 zener 400mW
12V zener 400mW
1N914
Mains Transformer 15 -0 -15 V 100mA
Si, S3, S4, S5, S6 SPST miniature toggle switch
S2
SPDT miniature toggle switch
S7
SPST miniature mains toggle switch
L1, L2
SC60 miniature Choke 100mH
T1
10kû
68kû
390kû
10kû
390kû
10kû
20mm Fuse 250mA anti -surge plus
panel mounting fuseholder (12mm
hole fixing)
2 way jack socket 6.5mm
Mains neon indicator
Ft
SK1
LP1
2.2k0
2.2kû
Printed circuit boards
16 pin DIL socket
14 pin DIL socket
8 pin OIL socket
Case type 65 -2523E (Veroboard)
Knobs with graduated skirt dia. 30mm
Vero Stand -offs type B. 19mm long
3
22kû
22kû
1
3
1
500kû
1
500kí2
3
4
10kí
25k0 linear
10kû log
VR11
D12D13 Bridge Rectifier 100
N914
1N914
1N914
1N914
1N914
1N914
1N914
Miscellaneous
68kí2
VR7
VR8
VR9
VR10
1N914
1N914
Skeleton Preset Subminiature Vertical
(22- 1419H)
Length single screened wire. Length 3 -core mains
lead. Rubber grommets. Vero half pins type
18 -0223
K
The author acknowledges the assistance
Capacitors
Electronics with this project.
Cl
100nF
Polyester
C2
C3
C4
C5
C6
C7
C8
C9
C10
lOnF
Mylar 10%
220nF
100nF
330nF
220nF
68nF
100nF
50nF
Polyester
Polyester
Polyester
Polyester
Polyester
Polyester
Mylar 10%
Ceramic
Ceramic
Mylar 10%
Polyester
Polyester
Polyester
Polyester
Polyester
Polyester
Mylar 10°%,
Polyester
Mylar 10%
Mylar 10%
C11
C12
C13
C14
C15
C16
C17
C18
C19
C20
C21
C22
4-7nF
4.7nF
20nF
100nF
150nF
47nF
150nF
47nF
33nF
lOnF
33nF
lOnF
40nF
C23
C24
C25
C26
CV
C28
C29
C30
C31
C32
C33
C34
C35
C36
C37
C38
C39
C40
C41
C42
C43
12nF
40nF
12nF
4.7nF
1
5nF
4.7nF
1
5nF
50nF
18nF
50nF
18nF
220nF
100nF
220nF
100µF
100µF
100µF
10µF
10µF
100uF
100µF
Polyester
Mylar 10%
Polyester
Ceramic
Ceramic
Ceramic
Ceramic
Mylar 10°%,
Polyester
Mylar 10%
Polyester
Polyester
Polyester
Polyester
25
25
25
25
25
25
25
V
V
V
V
V
V
V
Capacitors C19, C20, C21, C23, C24 and C25 are
the most important and 5% types could be used if
available (see text).
Polyester are Mullard C280 except C23, 25, 31 and
33 which are C296A.
54
of Watford
COLLATED LIST FOR RESISTORS
AND CAPACITORS
Resistors
1
3
1
Capacitors
680e
2
2.2k0
3.9kû
4
3
4.7kí
1.5n F Ceramic
4.7nF Ceramic
lOnF Mylar 10%
100kû
150kû
390kû
470kû
Polyester (Mullard C296A)
Polyester
It
1 20nF Mylar 10%
2 33nF Polyester (Mullard C280)
2 40nF Polyester
2 47nF Polyester
3 50nF Mylar 10%
1 68nF Polyester
5 100nF Polyester
2 150nF Polyester
4 220nF Polyester
1 330nF Polyester
6
1Mí
210pF25V
1
22M12
5
2
9
5
12
5
5
1
10
3
5
4
1
10kû
12k0
22ki2
27kû
47kû
56k2
68kû
2 12nF
2 18nF
100µF 25V
Practical Wireless, May 1976
IC3d
BASS DRUM
1,44011A
4
VR4 500k
R3` 150k
R5a
R7a
C2a
11_
BD input
from
C14
12k
%////i
C4a
pulse
input
C1747nF
+
R30
27k
R28
C 3a
Trigger
IC1 pin11 150nF
D7
1N914
i4 4011A
HIGH BONGO
11
VR5 500k
R39 1500
of a damped sinusoidal oscillator, comprising
'Twin -T' ringing oscillator utilising a NAND gate.
Fig. 5: Basic circuit
C20
33nF
C19
10n F
R36
12k
R37
47k
DB
1N914
For rhythms of 4/4 time and for the March and
Tango the number of counts per rhythm pattern is
32, each rhythm pattern covering two bars. The
tempo is thus variable from approximately 9 to 94
bars /min. In the case of rhythms of 3/4 and 6/8
time the counter resets after 24 pulses and there are
two bars per rhythm pattern giving a tempo from
13 to 125 bars/min.
The Shuffle, 2/4 time, has four bars per rhythm
pattern and resets after 24 pulses giving a variation
of 25 bars /min to 250 bars /min which is twice the
tempo of the Waltz and over 212 times that of the 4/4
rhythms, for the same setting of VR1. It is for this
reason that the tempo control covers such a wide
range and will need adjustment especially when
R43
C21 tOnF
R38
27k
390k
R41
10k
IC4G
LOW BONGO
i4 4011A
s
R47 150k
VR6 500k
R50 68k
R48 68k
c24
40nF
C23
from
IC1
-I
12nF
LB input
C22
pin14 40nF
46
R44
I
F---vv\--
C25 12nF
D9
7k
12k
I
Fig. 6: Circuit diagram left shows the five ringing oscillators for bass
drum, high and low bongos, claves and conga drum, All five circuits
feed into a common pre -amplifier.
The circuit below shows the various power requirements for the IC's
390k
R49
1N914
10k
i
IC4c
POWER SUPPLY TO
4011A
IC's
+12V
1
500k'
R55150k
VR7
R56 68k
R58 68k
CL input
IC1 pin12 C26
4'7nF
via S2
jjjfj
R59
C2915nF
+
54
7k
+5V
T C28
4.7nF
C27
1 5nF
from
010
14
14
14
¡Cl
1C2
1C3
1C4
10
7
7
7
1
IC4d
PRE -AMPLIFIER
4011A
4
From C13
VR8 500k
IC5
.
---VYV-R64 68k
R66 68k
R7010k
C 32
C31
18nF
CD input
from
¡Cl pinti
R60
12k
5030E
T 50nF
C33 18nF
R62
27k
D11
1N914
R65
OV
12V
CONGA DRUM
R63 150k 6
105
1M
R57
10k
'EN914
a
C35
C34
1O0nF
220nF
R67
390k
C36
220nF
Volume
VR9
10k
R68
Output
10k
10k
AM 04621
Practical Wireless, May 1976
55
However, a problem does exist in the case of the
high and low bongos. The frequency of operation
and therefore the capacitor values of these two
instruments is very close and 10% tolerance has
been specified in this instance. This still means it is
possible in an extreme case that the frequencies of
operation could be identical and if this does occur
5% types may be substituted to overcome the
problem.
In the second category falls the long cymbals,
short cymbals and maracas, for which the basic type
of circuit is shown in Fig. 7. Transistor Trlb is
switched on during the short trigger pulse from the
M252 chip and charges C2b. This capacitor then
discharges through R4b to the base of Tr3b. The white
noise produced by Tr2b by the zener effect of the
reverse biased base-emitter junction is also applied
to the base of Tr3b via C3b. During the discharge of
C2b, Tr3b can amplify this noise. The degree of amplification, however, follows the discharge curve of
C2b and therefore a damping of a variable length is
obtained depending on the values of C2b and R4b. The
inductor 1113 and the capacitor C4b allow selective
amplification of certain frequencies to obtain a more
realistic sound of the instrument being simulated.
The distinctive metallic sound of the snare drum
caused in the real intrument by catgut snares
stretched across the drum-head is realistically simulated by combining filtered white noise from this
circuit with high bongo. The long cymbal and short
cymbal circuits dispense with Trlb and differ only in
decay time. The maracas simulator is unusual in
that it is the only instrument in which the sound
increases gradually and then decays. This effect is
achieved by means of an integrator-differentiator
circuit D4, D5, R19, R2O and C8, see Fig. 4.
changing to the Shuffle. To facilitate the exact setting
of the tempo, control knobs of the type with a
graduated skirt are recommended.
The internal reset pulse of the generator chip is
only 2 to 3µS long so it is too short to light a
lamp. It is also necessary that the lamp should light
on the negative edge of the reset pulse which occurs
at the beginning of the bar. The down-beat monostable circuit, see Fig. 4, comprises C2, C3, R4, R5,
R6, R7, IC3a and IC3b. It lengthens the short downbeat trigger pulse to around 350mS by latching the
output of IC3b to '0' until C3 has charged up to
above the "1" input trigger level of IC3a. It operates
on negative -going pulses only and the resulting '0'
output from IC3b is inverted by the NAND gate
IC3c to switch on Trl thus lighting the LED.
Percussion Instruments
The percussion instruments may be divided into
two categories, those that consist of damped sinusoidal oscillations and those consisting of damped
filtered white noise. In the first category 'are
included the bass drum, high bongo, low bongo,
conga drum and claves. The general circuit shown
in Fig. 5 consists of a simple twin-T ringing
oscillator utilising a NAND gate which is adjusted
to a point slightly below oscillation by VR1a. The
different sound of each instrument is achieved by
choosing the correct values of C2a and C3a to
determine the required frequency of operation and
by regulating its decay time (damping) by VRla to
obtain longer or shorter sounds.
The trigger pulse from the M252 is a square wave
which must be differentiated by Cla and R2a and
allowed one -way entry by diode Dla to produce a
short pulse which is sufficient to set the oscillator
ringing but not to interefere with the damping of
the oscillation. Resistor Rla is necessary to keep the
input at earth in the absence of a command pulse
since the outputs of the M252 are open drain types.
Fig. 6 shows the circuit of the five ringing
oscillators used and gives values for the three
frequency determining capacitors for each instrument. The tolerance of these capacitors is not too
critical but it should be kept within 20 %, which is
reflected in the types specified in the component list.
IAM0463I
Tr2b
Pro-amplifier
The outputs of the nine instruments are mixed
and fed to the input of the pre -amplifier through the
preset potentiometer VR9, Fig. 6. The active element
of the amplifier is the ubiquitous 741 op.amp used in
the non -inverting mode. A simple variable low-pass
filter, C35 VRIO, acts as a tone control and the
output level is adjustable by means of the potentio-
meter VR11.
PART 2, to be published next month, will cover details of
the power supply, PCB's, construction and setting -up.
R6b
JL
Trigger
pulse
input
C3b=
Cib
Output
*Tr1b
Fig. 7: Basic circuit of
the 'white noise' instrument simulator.
Tr3b
Rib
".C4b
à
56
Practical Wireless, May 1976
MORE
5
ON RECENT DEVELOPMENTS
THE FLASHER
COMPUTER-FACILITY
If it's escaped your attention, the
LM3909 chip is well worth looking at
if you need some form of flashing
light. In its simplest form the IC
needs only a 1.5V battery and a
suitable capacitor to make a flashing
light which will keep going for a very
long time-like two years with an
akaline cell. One useful circuit
suggested by the manufacturers is
to mount the chip, I.e.d. and capacitor
into the base of a torch. The tiny
flashing light can be seen in the dark
making it easy to always find your
torch. Ideas for toys, models etc.
come readily to mind and I reckon
that this IC will fast become a
favourite with amateur constructors.
FOR £7.50
LIQUID CRYSTAL PICS.
Electronics and photography have
always been close allies for the
hobbyist. Of interest to both will be
the work being carried out at the
Hughes Aircraft Company. Researchers there are working on what
they call a light cell. The idea is to
enhance the image being reproduced.
To do this photographically is not
so easy, and present electronic
solutions are not ideal.
The Hughes approach is quite
ingenious. The light from the desired
image (i.e. the varying tones formed
by the brightness of the light in the
various parts of the image) is allowed
to strike a cadmium -sulphide layer
which modulates the resistivity of
the photoconductive layer. This in
turn varies the voltage which is
applied to a liquid crystal layer. The
characteristics of the liquid crystal
can be altered thus giving control
over the image which is finally
transmitted. Resolution is presently
60 lines /millimetre and the device
requires only 6V.
A new general -purpose microprocessor shortly to be introduced
by National Semiconductor, and
priced around £7.50 in quantity lots,
is expected to generate keen interest
in present users of Random Logic.
SC /MP is an 8 -bit PMOS microprocessor operating at 2 microsec
cycle time and requiring only a single
12V supply with a useful margin of
+2V. It generates its own timing on
the chip, and will be ideally suited to
simple control and timing functions.
Designers working with appliance
controls, building monitors, fuel injection units, traffic signal control,
word-processing systems, electronic
toys, etc. will find the SC /MP right
in both design and cost, claims N.S.
Multiple SC /MP can communicate
with each other when they share a
common bus. Logic on each chip
senses when the bus is in use, so
when one SC /MP ceases transmission (or reception) the next can
take over. If it declines, the next but
one is invited.
A simple control system can be
developed using one SC /MP and a
programme memory -which can be
selected from a wide range of standard memory parts. Such a system
could access up to 4 kilobits of
memory and could provide the control
logic for simple industrial systems,
TV games, small traffic- control
systems, etc.
I.R. HEADSETS
VIDEO DISCS
The video home -player scene has
taken on a new look. A large French
company recently confessed that it
is going into production with an
discinexpensive optical video
player. What is interesting is that
the company, looking some years
ahead, sees the distinct possibility
of cheap throw -away video discs
which will be sold at newsagents just
like magazines.
GAMING CHIPS
In a previous issue (Hotlines, Pracmentical Wireless, March 1976)
tioned tv games. US semiconductor
giant Fairchild has announced that it
is going into this area in a big way.
Plans haven't been completely revealed as yet but it would seem
promising for the home constructor
if this company were to start manufacturing chips specifically designed
for things like tele- tennis, tele -football etc. Please note; they haven't
started making them so don't look
for ICs yet a while.
I
A recent development in the West
German colour television market has
caused quite a stir among other
europeans. Apparently infrared audio
headsets are now becoming in-
OUR CQ "COLUMN"
If you wish to have a "CQ" request in
Practical Wireless, we would be grateful if
you could write it out in the same style we
print it. This helps us to help you by saving
time trying to take extracts from long letters
and deciphering names and addresses.
Thank you.
Practical Wireless, May 1976
creasingly common as a standard
fitment to the receivers. Another
application of the infrared audio
system is to teach children whose
hearing is impaired. The infrared is
transmitted to a minute IR receiver
which is an integral part of the headphones thus leaving one free to move
about anywhere within the range of
the IR beam. One German company
is readying a two- channel stereo
transmission system. The signals for
each of the two channels is modulated onto two separata carriers.
These are set at 200kHz and 280kHz.
These frequencies are then transmitted via the infrared beams.
Please mention
PRACTICAL WIRELESS
when replying to
advertisements
57
EQUIPMENT CASES
PIU)1)iJ(;'l'IOAT
LINES
ITT SOUNDERS
ITT are marketing a range of piezo
ceramic sounders. The smaller ones
shown in the picture comprise a thin
piezo -electric vibrator and solid -state
oscillator. One very special feature
of the units is their exceedingly low
power consumption with high sound
pressure level.
The circular device at the top left of
the
photograph is Model U25ORDID2H which gives a continuous
short pulsed or long pulsed tone
facility from 24V. Operating voltage is
5 -35V at 10mA with an oscillating
frequency of 2.7kHz. Sound level is
over 90dB. The small black sounder
(centre) -the U5 -35R runs at 4mA
with a continuous tone only. Output is
over 70dB. The bottom left unit
(U1- 50RD2) has continuous or long
pulsed tones and runs on 12V at
10mA. The bottom right unit (U35DR) is a 24V continuous tone
sounder which draws 8mA.
The sounders make very good
alarms for use inside the home i.e.
they could be wired to fire alarms,
smoke detectors, mains failure alarms
for freezers etc. etc. and their very
low current consumption makes
them ideal for this purpose.
The horn -type sounder RHA 102
(top right) is a real "ear -splitter"
which incorporates a sensitive drive
unit and solid -state oscillator amplifier. Two separate tones are provided- warble at 1200Hz- 1700Hz at
180 c.p. minute, and continuous
1000Hz, and these can be used
individually by connecting the appropriate pair of wires to the 12V d.c.
supply. Current consumption of this
model is 400mA and it pushes out
98dB of noise making it eminently
suitable for applications where warning signals are required e.g. fire and
intruder systems, factories, hotels,
vehicle alarms and so on. Prices, not
yet fixed are believed to be quite
reasonable. Further gen by sending
a stamped addressed envelope to
Mr. K. W. Stanton, ITT Components
colin riches
BENCH GRINDERS
Industrial power tool manufacturers,
Wolf Electric Tools Ltd., have introduced two new 5in (125mm) Bench
Grinders to complement their bin.
and 8in. industrial model range. The
new machines are designed for light
industrial and home workshop use
and those of you who are still of the
"Chassis bashing fraternity ".
Model 8252 is fitted with an 80 grit
fine grinding wheel and a 60 grit
coarse wheel while the more versatile
model 8159 is fitted with a 80 grit
grinding wheel and an 8mm chuck,
enabling its use with small accessories for polishing, sanding etc.
Both models are supplied with
adjustable tool rests and eye protection for grinding work. Recommended price of either model is,
£41.95, excluding V.A.T. Wolf Electric
Tools Ltd., (Dept. P.W.) Station House,
Harrow Road, Wembley HA9 6TJ.
H.M. Electronics have announced
two rather attractive equipment cases.
Model DC.1 (with the sloping front)
which, say the makers, was designed
with digital clocks in mind, can also
be used for mixer units, electronic
dice or some of the many projects
published in our pages. The second
case is the Mini -bec case which
measures lin x 3in. (or the decimal
178mm x 76mm). Both units would
give home -built equipment a really
professional finish for they are well made in aluminium with black crackle
tops with teak end sections. In
addition, the DC.1 has a green front
panel. Prices: the DC.1 costs £3.75
+ 75p post and packing incl. VAT
and the Mini -bec is priced at £2.99+
75p post and packing incl. VAT.
Further
information
from H.M.
Electronics, (Dept. P.W.) 275a Fulwood
Road, Sheffield S10 3BD.
Group Europe, Standard Telephones
and Cables Ltd., Materials Division,
(Dept. P.W.) Edinburgh Way, Harlow,
Essex SM20 2DE. Phone Harlow 26811.
58
Practical Wireless, May 1976
ADC ACCUTRAC
A unique electronic turntable -the
"Accutrac" -operated by remote
control -has been introduced by
Audio Dynamics Corporation, a
subsidiary of BSR Ltd.
The Accutrac 4000, the first of three
units on the market comprises three
separate but interrelated component
pieces; the automatic direct drive
electronic turntable, a remote receiver
and a hand -held cordless transmitter.
From the comfort of an easy chair,
listeners can programme exactly
what they want to hear on a given
album by selecting tracks indicated
numerically on the transmitter. The
message is then transmitted to the
in
is
located
which
receiver,
convenient proximity to the turntable
and the receiver in turn activates the
turntable's arm, which places the
stylus precisely at the beginning of
the track selected by the listener.
The receiver's L.E.D. (Light Emitting
Diode) winking "eye" lets the listener
know that the information has been
received and held in total memory.
Up to twenty -four commands can
be programmed in any order required.
The transmitter can also be pro-
grammed to reject, cue, repeat and
clear, as well as play, in fact virtually
all you have to do is to place a
record on the turntable. Track
selection can be determined by a
quick look at the album jacket and
favourite selections can be repeated
over and over again without the
listener even having to move an inch.
How does the Accutrac actually
work? The Accutrac process begins
with the logic circuitry built into the
turntable, a direct drive unit. In the
Accutrac system, there are electronic
speed- sensing circuits within the
motor itself, constantly monitoring
the turntable's speed accuracy and
instantaneously correcting the speed.
In a sense, Accutrac has eyes.
A tiny solid -state infra -red generator
and detector is built into the special
ADC LMA -1 cartridge (an advanced
version of the XLM). The generator
focuses a tiny beam of infra -red light
onto the record and senses the
surface of the disc. Although the
arm is raised, lowered and moved
automatically by its own servo -motor,
it always tracks the groove with
perfect freedom because from the
instant the stylus touches the record,
the arm is totally decoupled from
the servo -motor and controls.
Separate control circuits for each
speed allow individual adjustment
and switching from 33 to 45 rpm now
involves just a
simple reliable
switch -no mechanisms. In order
to prevent floor shake, footsteps or
acoustic feedback from reaching the
stylus in the groove, the arm and
on
motorboard are suspended
springs that have been computer calibrated to provide maximum
isolation and security. Price is
about £300. BSR Limited (Dept. P.W.),
Powke Lane, Cradley Heath, Warley,
West Midlands, 864 5QH, England.
Diagram showing the infra -red Tx/Rx (left).
The Accutrac deck with remote control
Tx/Rx (below).
FUNCTION CALCULATOR
WITH CONSTANT AND
8-
MEMORY ANNOUNCED
BY
T.I.
A new 8- function electronic calculator recently launched by the European
Calculator Division of Texas Instruments Limited is designated the
TI- 2550 -II. The new calculator features the basic five functions -add,
subtract, multiply, divide, and percent -with an automatic constant on
all five functions plus a full four -key
memory (memory plus, memory
minus, memory recall, and. clear
memory). In addition it features the
widely used slide rule calculator functions of square root, square and reciprocal. Recommended retail price
of this new calculator is £29.95 inc.
V.A.T. and accessories.
The "reverse key" is especially
useful to divide the quantity in the
memory by the quantity in the display.
The square root, square, and reciprocal keys operate only on the
displayed quantity; they do not
complete any pending operation.
Thus, the calculator can easily solve
problems such as the square root
of the sum of squares without using
the memory.
For maximum readability, the negative sign is always displayed immediately to the left of the first displayed
digit. A ninth character on the
extreme left of the display is used to
indicate a quantity stored in the
memory as an error and overflow
indication.
Packaged in a 5.8 by 3.2 by 1.25in.
(14.7 x 8.1 x 3.2cm) case and weighing less than 8 ounces (230 grammes),
the TI- 2550 -II comes with battery
pack containing two fast- charge
nickel- cadmium batteries, the AC9900
adapter /charger and owner's manual.
Texas Instruments Ltd., (Dept. P.W.)
165 Bath Road, Slough SL1 4AD Berkshire. Telephone Slough 35544.
Practical Wireless, May 1976
59
SPECIAL PRODUCT REPORT -continued from
page 31
adjacent to the coil, keeping the connecting leads as short
as possible, thinking that these new "electrics" might cause
interference to the car's radio. In the event it was possible to
switch from normal to electronic ignition without any
difference being noted to the general noise level on the
radio. The holes in the box were drilled out to take +in. bolts,
one fitted with a soldering tag to take the black chassis lead
from the unit. All existing push -on tags were retained,
spade tags being fitted to the leads from the unit. At any
time the unit can be removed and the wiring replaced in a
couple of minutes.
ON THE ROAD
The installation instructions are very good. If more than
one wire is found on the "SW" terminal of the coil all should
be removed and connected to the blue wire from the unit. A
short piece of insulating sleeving was fitted over each
exposed connection and the wires taped together neatly.
Some slack was left in the wires to allow for movement of
the engine on its mountings.
Oscillator
350VDC
Rectifier
SW
Thyristor
Coil
1
12VDC
Contact
breaker
CB
Tri gger
circuit
of rough running at low speeds especially when the foot
was lifted from the accelerator. At this point no attention
had been paid to the sparking plugs or contact breaker
which had been in use for several thousand miles without
attention other than checking the gaps from time to time.
CONCLUSIONS
New plugs and contact breaker set were fitted and the
rough running disappeared, gaps being set at the usual 25
and 15 thou respectively. Increased gap on the plugs is
usually recommended with electronic ignition but this has
not been tried yet. Daughter normally keeps a record of
petrol bought and miles run so this was very useful in
trying to assess whether there was an improvement in
petrol consumption. It is unfortunate that a lot of rubbish is
written about sensational improvements in this field with
electronic ignition but it is seldom borne out in practice.
An improvement of about two miles a gallon was found but
a lot more mileage will have to be run before a definite figure
could be given.
No doubt if the Herald were kept in tip -top order with
frequent checks on engine performance with test equipment
the electronic ignition would not make so much difference
to its performance, except at high speeds, but the Herald
was an ordinary car, receiving less care than it really deserves, yet it benefited considerably from the electronic
ignition. Considering the price of the Bi- Pre -Pak kit it is a
very good investment indeed.
The Super Spark Ignition Kit is available from Bi- Pre -Pak
for £9.09 including VAT and post and packing from 222
A.E.D.
West Road, Westcliff -on -Sea, Essex SSO 9DE.
Chassis
FK1621
Basic circuit
of a capacity discharge ignition system.
variations of this theme to be found.
There are many
The Herald, normally driven by the daughter of the family,
was left out in the open during the cold spell and the engine
started every morning after the second go on the starter
plus half the usual amount of choke. This was a distinct
improvement on the normal performance in average temperatures. To the reviewer this aspect of electronic ignition is
most important with the consequent saving in wear and tear
on the battery and the starter. Performance at speed was
noticeably better, the car seeming to have more power and to
run more smoothly in the 60 to 70mph range, no doubt due
to the virtual elimination of the contact breaker bounce
problem at high engine speeds. There was a certain amount
ISSUES WANTED
..issues of P.W. (either
1969 or 1970) containing details
of a short wave converter (used RCA CA3028). -W. D. Smith,
46 Santon Way, Seascale, Cumb.
..issues of P.W. containing details of mods to the 19 set
(? 1960). -D. Collings, coo Glossop School, Talbot Rood,
Glossop SK13, Derbyshire.
..P.W. March and April
S. Brown,
M24 3JG.
12
1971.
Waverley Road,
Also P.W. May
1972.
Middleton, Manchester,
..P.W. July 1961 and August 1961 -G. Farrer, 16 Duncan
Road, Gillingham, Kent.
INFORMATION WANTED
..manual and circuit diagram for Pye Ranger 2207V.C. Sedgwick, 38 Eaton Road, Kempton, Beds., MK42 7RP.
..on Pamphonic type 601A, 601B (or Cossor 601A and
601B) amplifiers.
Evans, 29 Malton Road, Liverpool,
L25 8QU.
-D.
EQUIPMENT FOR DISPOSAL
The completed unit, ready for installation in the car. The switches are
shown in their 'anti -thief' positions. Electronic ignition is operative
with both switches to the right and normal ignition when they are to
the left. A small neon lamp protrudes through the grommet, bottom
centre, lighting when the unit is functioning properly.
60
..60 Practical Wireless's from 1971 to 1975, resistors,
capacitors, (fixed and variable), transistors, (PNP and NPN
with long leads), speakers (3 ohms to 35 ohms), valves
(DL96, DAF types). Please send a stamped addressed
envelope for a list. -J. Owens, 26 Ardd Fawr, Dolgellau,
N. Wales.
Practical Wireless, May 1976
How to get a reputation overnight for
making Hi Fi equipment as good as ours.
To be perfectly honest, it's not that
difficult.
Simply go out and buy a Goldring CK2
turntable construction kit. Follow the simple
step by step instructions.
And in no time at all you'll be the proud
owner of a superb, hand built, precision
engineered deck.
Which can hardly fail to make your
reputation amongst those who know about
HiFi. And all acheived with the minimum
capital outlay: around £28.00.
The Goldring CK2 kit is, in fact, based
around the rather more widely known G102
turntable.
Which means it's belt driven, to reduce
wow, flutter and rumble to an absolute
minimum. (The same system most really
expensive decks employ.)
The pick-up arm features a viscously
damped raising and lowering device.
For the protection of your records,
there's an anti -skate mechanism. And with an
Practical Wireless, May 1976
easily adjustable playing weight, the arm will
accept a wide range of cartridges, such as the
Goldring G800.
A final touch is that both the on -off
function and speed selection are via neat
rocker switches.
If you fill in the coupon, we'll send you
our free colour brochure, which describes the
CK2 construction unit in detail.
And if you're
serious about HiFi,
you couldn't hope
to ask for a better
start than that.
Ro: Goldring Limited. lo Bayford.Street, Hackney, London E2t 3S17-1
Please tell nie more about the Goldning CK2 Construction unit.
Name
Address
PW 576
O Gold ng
61
stage requiring a double 4.5V battery, and since the
PP11 or similar now costs 85p, replacement is a
big item in a modest budget. Here again, it is possible
to buy a ready-made mains unit giving two 4.5V outputs, but they are more expensive than the single
9V units, not so easy to make up from the spares
box, and I have never seen a kit for one.
The solution is, really, to convert the output stage
of such a set from double 4.5V to single 9V working.
Even if the user then continues to use batteries,
this will bring down his replacement costs by over
30% from 85p to 52p and of course there are cheaper
9V mains units available and they are much
simpler to make up. I recently came across an OAP
faced with the problem of the expense of the Pll
and I managed to convert his set from double 4.5V
to single 9V working in what proved to be an extremely simple manner, once the PCB had been
extracted from the case and examined. The set
proved to have a fairly common split battery, push pull output stage, as in Fig. 1. This had to be converted to single battery working with as little
disturbance as possible of the existing PCB and the
controls. In fact, it proved possible by re-soldering
only two connections:
Battery
Economy
h
B.B.RAFTER
Transistor
Radios
of those hardest hit by the general heavy
in dry battery prices over the last few
years are the "senior citizens" who live on a
tightish budget and rely to such a great extent for
news, entertainment and especially "company" on
their transistor portables, sometimes themselves
quite senior! It is, of course, possible in many cases,
though not in all, to replace batteries by a small
mains unit and this will soon repay its cost by
savings in replacements at anything between 52p
and 85p a time. Perhaps the easiest sets to convert
in this way are the portables of any vintage using the
PP9 or equivalent battery, as this can usually be
replaced by a mains unit of identical size, either
bought complete, made up from data published, or
from kits advertised or from the spares box.
Many portables,' however, dating from the days
before complementary symmetry in output stages,
have a split secondary "single- ended" push-pull power
-
SME
OME
.
Lead A from the speaker in Fig. 1 was cut where
it entered the 4-pin battery plug and re- soldered
to point X on the double pole switch at the
back of the volume control.
Lead B from the speaker was transferred, on
the PCB, from the negative side of the capacitor
(100uF) to the positive side, at point C.
These changes thus produced the standard single
9V output stage, as in Fig. 2. All that remained was
to change the battery plug from the original 4 -pin
(for two 4.5V outlets) to an ordinary 9V type,
using the cut-away top from a defunct PP9 battery.
The conversion was then complete, much to the
pleasure of our old friend, for whom it will now
be possible, if he so wishes, for me to make up a
small 9V mains unit to enable him to use his beloved
portable at minimum cost.
oltDL__
On /Off
switch
Input
1/V
Fig.
62
1,
left, shows
a
I
L
--
_
J
typical output stage using two 4.5V batteries. Fig.
2,
right, is the same circuit converted to operate from
a
single 9V battery.
Practical Wireless, May 1976
'SPECIALIST' RANGE
Models for
purposes
5
5
FANE CRESCENDO COLOSSUS
/
Model
DISCO
Range 22 Hz -3.2 kHz
£9995
Total Flux 366,000
For front or rear
mounting
All have
Bass Resonance 23 Hz
Rec price inc. VAT
4" POLE
60
Weight 31} lb
200w R.M.S.
18" DIAM.
Illust.
ELITE RANGE
CRESCENDO 12A
I2L
ROBUST
CAST
ALUMINIUM
CHASSIS and
EXTRA HIGH
POWER COILS.
I8A
18 BASS
PI
COLOSSUS
Rec. Prices
from
£49.30
inc. VAT
PROFESSIONAL
MUSICIAN
HIGH
FREQUENCY
HORN UNITS
Available in 8 or 155E Imp.
2 Year full Guarantee
*12" DISCO 60
Rec. Price
Linen cone surround
£25.95
Extra Large TWEETER
I2" GUITAR 60L
I2" GUITAR 60B
£24.75
For use in multiples
£24.95
Bass
15
15 BASS
01
OUTSTANDING
QUALITY FOR THE
DISCRIMINATING
for
1R.M.S.
2 BA SS
ALL 100 Watt
CRESCENDO
Guitar
MODEL 910 Mk II
And don't forget our fast selling
and reliable 'Budget Speakers'
£37.75
`Available in handsome
Vynide & Vynair
covered Cabinet
£43.50
filter. Rec. Price
'POP' 60 15" 60w £23.95
15 12" 15w 17.95
33T I2" 33w 111-50 'POP' 70 IS" 70w £25.95
50/2 12" 50w £ I4.99 'POP' 100 18" 100w £39.95
55/2 12" 60w 120.95
Above are Rec. Prices inc. V.A.T. Guarantee is for 2 years.
I2" PAIO
BASS 70 70W
For all Bass Instr
watts with
recommended
'POP' RANGE
'POP'
'POP'
'POP'
'POP'
£24.75
General Purpose
All above 60w R.M.S.
I5"
Rating 50
MODEL 920 Mk II
significantly increased
sensitivity. Racing with
recommended filter 100 watts
(as illust) Rec. Price
Distributors (Wholesale & Retail Trade)
LINEAR PRODUCTS LTD.,
with all enquiries
Electron Works, Armley, Leeds.
Manufacturers enquiries to: FANE ACOUSTICS LTD.,
286 Bradford Road, Batley, Yorks.
Please send SAE
049.95
HPXI HIGH POWER CROSS -OVER UNIT
Suitable for above Horn Units Rec. Price £2.70
Prices shown correct at Mar. S, 1976
TRANSFORMERS
MAINS SAFETY ISOLATING
All types
Primary 240V. Sec. 120V or 240V.
Please state which type you require.
are screened and Centre tapped to earth.
PLUGS
V.A.
(watts)
OPEN
TYPE
P. á P.
CASED
TYPE
£
p
£
308
50
100
1.10
1.18
1.34
1059
1218
O.A.
O.A.
O.A.
O.A.
O.A.
18-65
26-00
29-65
35-00
55-00
CASED TYPES
5
24V
25
5
£
p
26
1.58
2.05
2.52
3.76
430
493
6.35
1.20
10
QUANTITY
DISCOUNTS
2
P & P
130
8
3
1
3777
---
3
1
1
3
1
O.A.
O.A.
O.A.
O.A.
O.A.
O.A.
1-20
1-20
2.40
3.60
2.70
5.10
MINIATURE TRANSFORMERS
4
6
2
6
1
30-80
9 27
1
25
50
1ß0
Sec. volts
200
0-602
1A
0-9 x
0-9 x
0-9 x
2
2
330
500
2
IA
0-15
x 2
200
300
0-20x 2
0-20x 2
0-15-27
to 24 off Basic Price
to 49 off 25^%, off Price
to 99 off 5% off Price
100 to 249
mA
3-0-3
off 10°%, off Price
x 2
1A
IA
PRICE
£
1.37
1
8
1.34
1.83
2.60
1.30
1.72
3.08
3 86
P&P
P
25
45
26
45
52
25
52
72
72
F.M. Tuners. 8- transistor
Isis
PEKE
with Stereo-decoder
and L.E.D. Indicator
Aircraft-band receiver. Just place near any radio
Echo-chamber. (Endless tape). Variable delay
Field- strength indicators. 1 -250 MHz
Stereo Amplifiers complete. 3-watt. 8 -ohm
10 -watt Amplifiers. 12 volt D.C. 3/8/15 -ohm.
Cartridges. Acos GP 104. Ceramic /Diamond
Cartridges. Acos GP 101. Crystal /Sapphire /Compatible
Speakers. 21^-8 -ohm
Speakers. Car Stereo. 8 -ohm, 5 -watt. In cabinets
Dynamic Tape Mikes with remote -control facility
Crystal Tape Recorder Mikes
Crystal Mike inserts with bracket
indicators. 12 -volt L.E.D. in Chrome Bezel
"Bargain Bags" 41bs Caps /Resistors /Transistors /Diodes
Controls. Volume /Pre-set (Rotary á Slider) Assorted 100
Transistors. 20 NPN /PNP. All new and marked
Transistors. 100 NPN untested.
100 Germanium untested
Diodes.
100 Silicon untested
Diodes.
100 Zener untested
Diodes.
"Pack 1" 100 resistors. 100 ceramics. 100 diodes
"Pack 2" 100 resistors. 100 ceramics. 100 polystyrene
"Pack 3" 100 resistors. 100 S /Mica /Ceramic. 100 Polyester
ALL ABOVE ITEMS PLUS 25% VAT
Camping Lights. 21"
Fluorescent
12 -volt
"Disco type
3- Channel
13 -watt
Lter 60 £1090
E3-911
£5.9
E3-311
E275
13.110
2
£.100
50
connection needed to amp
Multimeters. AC 0- 1000V. DC 0-1000V., 0 -100 ma. 0- 150kohm
Multimeters. AC 0 -500V. (10 ranges) DC 0 -500V. (12 ranges)
DC Current 0-25ua to 0-10 amps (10 ranges)
Resistance 0- 100ohms to 0- 16Mohms. (4 ranges)
Panel Meters. 0 -50ua. 2}" o j"
Soldering Irons. 15 -watt. Pencil Bit.
Servisol Switch Cleaner (with Snorkel)
Copper-clad Fibre Glass Board. Single- sided. Square toot
PLEASE ADD 8% V.A.T. TO TOTAL PRICE
S. G. Wright's Ltd., Bishop House Works, Rylands St.,
BURNLEY, Lancs. BB101RG Tel.
26934
IE7
00
00
MILWARD,
021 -327 2339
Alum Rock Road,'
Birmingham an 3DR
369
£4.90
0.110
£1750
£3.50
L
£1130
£2.511
E1-20
£0.50
£1N
£1.25
E1.30
£0.30
£0.40
- - - - - --
F.
S0
£1-00
£1-00
Developer for same
Ferric Chloride for etching
ALL ABOVE ITEMS PLUS 8% VAT
lei.
£0.35
£2.50
£0.90
£0.90
£0.20
£0-35
£4.00
£2.50
£1-00
Et-00
E0.50
£0.50
£100
Double-sided
"Fatolak" Light sensitive spray for printed circuit making
G.
£160
£050
£0
£111
12" 8-watt
flashing light units. Built -in mike. No
£3450
2.
1
250 to
499 off 15% off
999 off 20% off
500 to
1,000 to 1,999 off 25% off
2,000 and over 30% off
We manufacture Power Transformers to customers own special requirements,
please send details of any Transformer you may require custom built. All
queries must be accompanied by S.A.E.
Practical Wireless, May 1976
NORMAL
FOR
CASED
TYPE
complete
Primary voltage 240V
16
20
1
4
2325
5185
7535
8
12
2
CARRIAGE
set
44-30
45
45
62
62
85
88
1
amp
15
These are of extremely high quality to British Standard
Specification, with resettabie fused primary winding, and
are fitted with covered outlet sockets. Housed in steel cases
with carrying handles and 3ft of 3 core cable.
12V or 24V
Primary 240V
Please state which voltage
AMPS
PRICE
12V
amp
62
70
s0
4.53
7.26
8.80
200
250
350
500
750
1000
1500
2000
3000
SOCKETS
5
POSTAGE: Below
£10
50p
I
Above £10 Free
63
GREENWELD
443 Millbrook
Southampton
Road
SOLENT AUDIO SYSTEM
to this address please -callers only to 21 Deptford
Ot- 692 2009), and 38 Lower Addiscombe Road,
Croydon (Tel. 01- 688 2950).
All mall order and callers
Broadway,
SE8
(Tel.
QUALITY' STEREO SOUND!
Tel:(0703) 772501
SO1 OHX
PC ETCHING KIT Mk II
Contains lib Ferric Chloride,
£5.95
down
IPRICE OFFER!
AL"1
MULTIMETERS
100
ins copper clad board, DALO
Quick Dri Etch resist pen, abrasive
cleaner, 2 miniature drill bits, etching
dish and instructions. £3-IS
7Ib BARGAIN PARCELS
Hundreds of new components -pots,
sq
resistors, capacitors, switches, PC
Boards with transistors, diodes and
zeners, loads
Only E3-25
of odds
and
ends.
TRANSISTOR PACKS
asstd. mainly out of spec. transistors, mostly unmarked-NPN PNP
plastic, 105 TO18 RF AF Small
signal and TO3 power devices.
About 75% useable devices. Only
E1.1111. 1,000 unmarked t N4148 diodes,
95% OK. Only £4.N. 100 unmarked
BC108, untested £2-SI. 10 out of spec.
200
2N3055 E1.
COMPONENT PACKS
400
250
100
200
asstd. carbon resistors
Hi- Stabs, 1, 2, 5% } -1W
Wirewounds 2 -15W
£1.SO
MODEL LT22
Probably one of the lowest priced
meters featuring a mirror scale,
overload protection and 20000 ohms
per volt sensitivity. A modern styled
meter with unusually clear scale
markings. Ranges: DC Volts 0-0.52.5-10-50- 250 -1000 AC Volts 0- 10 -50250 -1000 DC Current 0.50, A -25mA250mA
Resistance
0- 50k- 500k -5M
(Mid Scale 300- 3k -30h) db's 4 ranges
-20db to +42dB. Size 130 x 90 x
£000
42mm.
E200
Miniature resistors, }, } and }W,
mostly carbon film
E1-10
200 poly, mica, ceramic caps
LI AO
100 Polyester, -01 -2.20F
EI.30
200 miniature electrolytics, but many
unmarked so only
£1.35
15
Air- spaced and compression
trimmers
LI .10
15 Useful switches, micro, toggle,
COMPUTER PANELS
Large quantity always available; alb
asstd. LI-75; 71bs £3.0S; 56Ib EIS.
Pack with about 500 components Inc.
at least 50 transistors LUMP; Pack
with 12 High quality panels, inc. IC's,
power transistors, mulliturn trimpots
hundreds of small signal transistors,
resistors, zeners, capacitors, etc.
Only E275.
7400 IC pack -20 74 series IC's on
panels E140.
PE Gas Ignitor Kit, as featured In
July 75 edition. Still only £3-00.
FERRIC CHLORIDE
Anhydrous technical quality in
I lb
double sealed packs. lib 85p; albs
E1
10;
101bs E4'81); 1001bs E30-00.
about
8
pieces (All 0.1" if requested)
LI 40.
DEVELOPMENT PACKS
50V ceramic plate capacitors, 5 %. 10
of each value 22pF to 1000pF, total
210 caps. E3-1111.
CR25 carbon film 1 /3rd watt resistors,
5%, 10 of each value 10 ohms to 1M
Total 610 resistors E7.50. Electrolytics, wire ended 25V working 10 each
of: 1, 2.2, 4.7, 10, 22, 47 and 100mid.
70 capacitors
for E3 -1111. 400mW
zeners 5%
10 each 3V to 30V, 260
In all. Only E14.00.
TRANSFORMERS
All have mains primaries.
6-0 -6V
100mA £1.00; 9 -0-9V 100mA £1.07;
12- 0-12V- 50mA 05p; 12-0-12V 100mA
LI -OS; 24 -0-24V 500mA E2.0S; Multl-
tapped transformer to give 3, 4, 5, 6,
8, 9, 10, 12, 15, 18, 20, 24 or 30V, or
12 -0-12,
or 15 -0.15V. IA version
E3-IS; 2A Version £445; 30 -0-30V 1 A
£35; 6-0-6V HA LI-SS; 12 -0-12V 1A
E2-IS; 25V 1.75A E2.00. 29V 50mA
8Sp; 12V 150mA 03p. Type LGC: 17V
at 2.4A; 15-7V ar 1ß5A and 12V a
0-5A E2-SO.
ODDS AND ENDS
975kHz FT171 B Xtal Sep; 20 33k or 1.8k
1% resistors 2Sp; Connector blocks,
12 way 2A or 5A, both 21Ip; Magnets,
ceramic 9mm dia. x 10mm long with
2.8mm hole through the middle. 10
for 15p; Capacitors: 20000F 10V vert
mntg, long leads 12 for LI N; 100 +
4000 275V 43mm die x 112mm long
Np; 160000F 25V 52mm die. z 112mm
long 6Sp; Telephone inserts, 20(1
balanced armature unit 309; 250V 2 }A
bridge red Ssp; 50V 1A Sop;
tr
today.
Chassis only available for cash at £4200.
Full 12 months Guarantee.
An
MODEL C7017
exceptionally sensitive
Twin
Phono Socket sp; Crystal Mic Insert
die Up.
CALLERS WELCOME.
Access and Barclaycard
telephone orders accepted
meter,
100,000 ohms per volt, that will prove
its worth in a very short time. It fea-
tures 4 ohms ranges, measuring ul to
megohms and has a mirro scale.
Ranges: DC Volts 0-05-5-25-50-250 -
weirStereo
100
headphones supplied with every complete order
AC Volts 0- 10.50-250 -500 -1000.
DC Current 0- 100A- 2.5mA -25mA500mA.
Resistance 0- 10k- 1M -10M100M (Mid Scale 130- 13k- 130k -1.3M)
dB's -20 to +62. Size 152 x 102 x 44mm
1000.
PW /5/76
LONDON N14
SIGE SOUTHGATE
01- 882-1644
VEROBOXES 6 CASES
x 1400 40mm £2-110
1411, 205 x 140 x 75mm£3. 2S
1412, 205 x 140 x 110mm
Case type 1410, 205
14.20
Plastic Boxes -Processional quality,
two tone grey polystyrene boxes with
ENGINEERS
threaded inserts for mounting PC
boards.
Type 2518, 120 x 65 x 40mm £1.52;
x
50mm
LI .75;
188 x 110 x 60mm £2.40; Sloping
type: 220 x 174 x 100/52mm E4-211.
2522,
front
INTERCOM UNIT
Chassis 230 x 155mm with Celestion
ohm 110mm speaker, small buzzer,
pole 4 way switch, line matching
transformer, 10 way terminal block,
3
3
100k pot, etc. £2.00.
RF
UNIT
A compact tuning unit containing
z CV4063 and 3 x CV4014 with
screening cans, and a beautifully
made 5 gang tuning capacitor, twin
stator type, silver plated, with padders
on each section. Also numerous
coils, R's C'a, etc. Only £2-SO.
2
HEAT SINK
Large finned matt black aluminium
heat sink 230 x 200 x 35mm with 4
silicon power transistors, aim. to
2N3716, and 16 1 ohm 5W resistors.
£3-N.
YOURSELF FOR A
BETTER JOB
8t
ój./
easily removable reeds in 3580 ohm
coil SOp. Plug In relay, B7G base.
17mm dia. x 42mm long. 10ko coil,
1c /o contact 40p.
SWITCHES
16A 250V on /off rocker 20p; 10A 250V
on /off rocker with built in neon, 40p;
Push -on, push -off DPCO switch ISp;
10A 250V rocker, OPCO Biased 25p;
4 pole 3 way rotary switch, 32 mm die.
25p; Bank of 20 open construction
SPCO microswitches, overall length
225mm, useful as cheap keyboard
substitute. Only £130.
WIREWOUND POTS
30k 5W; 200(1 4W; 10k 3W; 1k 3W;
50(1 3W; 900 3W; 680 3W; 800 3W,
100k 3W. All 25p each, any 10 E2. 00.
PRACTICAL ELECTRONICS FOR INDIVIDUAL COMPONENT PRICES
All prices quoted Include VAT and UK/BFPO postage. Most orders despatched
on day of receipt. SAE with enquiries or for List please. Send 10p for Multi meter
catalogue-free on request on orders over £3. Official Orders accepted from
Schools, etc. Export /Wholesale enquiries welcome. Surplus components
always wanted.
IS
81
II
CHOOSE A BRAND NEW FUTURE HERE!
TWO or
Build As You -Learn
PRACTICAL
It AGIO
AND ELECTRONICS
(with kit)
Electrical
Engineering
Electrical Installationsand
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Thin helpful guide to success should be
read by every ambitious engineer.
Send for this helpful 44 page FREE book
now. No obligation and nobody will call
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ever did.
SICUT OUT THIS COUPON
RELAYS
Miniature plug in types: 1250 ohm
4c /o 409; 700 ohm 4c /o Sip PO 3000
type: 650 ohm 12V, with 6 heavy duty
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WIT"
Do you want promotion, a better job,
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I
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state sub,ecl of interest. Post to the address below.
Electronic
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London, EC2Y SEJ Tel: 01-628 2721
I
II
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SEE
64
IDO CHASE
Sit Tilhones:
£15.30.
2520, 150 x 80
VEROBOARD
100sq ins asstd. sizes and pitches,
ing long medium short and Stereo FM wavebands. Separate
Base and Treble controls. 30 watts total power output
(frequency response 25 -20,00 Hz) AFC Switching, Tape
record and playback facilities. Dimensions 18 1" x 9" x 31 ".
The very latest BSR automatic record deck with cue and
pause control. Two matching elliptical speaker units.
Order early limited stocks available cash price £59.95.
Credit Sale £5.95 deposit 9 monthly payments of £7.00
(Total Credit price £6895). P. & P. 13.00. Send £8.95
E1.40
rocker and rotary. £2.20.
35 Crystals, mostly HC11 U, at least
30 dill. frega. 4-8Mhz £1 -N.
'Stereo Tuner Amplifier chassis with AM /FM radio cover-
Other subjects
Accredited by
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An.
Member of A.B.C.C.
I
1
HOME OF BRITISH INSTITUTE OF ENGINEERING TECHNOLOGY
Practical Wireless, May 1976
EDITORIAL ANNOUNCEMENT
PRACTICAL
WIRELESS
P C B SERVICE FOR READERS
Our new PCB service is well under way and we are now able to
add PCBs for two popular projects published prior to December
1975. All boards, except SRBP, are epoxy glassfibre, drilled and
roller- tinned.
[To:-
READERS PCB SERVICES LTD, PO BOX 11, WORKSOP, NOTTS
Please supply PCB /s as indicated by tick /s in box /es
Issue
Project
Mar
Electronic Organ
(set of two)
Electronic Clock
(set of three)
75
Sep 75
Dec
Dec
Dec
Dec
Dec
Price P/P
Ref
AM0315} 7,80 +
A M0318
A M0387
AM0389
+
15
098 +
12
+
+
+
12
2.40
A M0392
75
DN0792
75
DN0793A 0.98
1.15
DN0798
DN2/JM 0.98
Radio -Pickup Link
Random Number Selector
75 Sound -To -Light Display
75 12V PA System
75 Disco System, Amplifier
25
12
12
o
o
o
o
3.40 + 18
each AM0421
required)
270 + 18
AM0423
Modulator
Light
Dec 75 Disco System,
SRBP DN1/JM 2.25 + 18
Jan 76 Music Box
glassfibre DN1/JM 300 + 18
AM0419 350 + 18
Jan 76 Emergency Light Unit
AM0438 1 19 + 12
Calibrator
Mar 76 CMOS Crystal
DN4/JM 1-92
Apr 76 DF Receiver
+ 15
DN5/JM}
(set of two)
1.08
AM0443
+ 12
Apr 76 Wobbulator
2.33
+ 15
AM0441
Synchroniser
Auto.
Slide
Apr 76
VAT.
include
Prices
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or
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for
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is
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payable to READERS PCB SERVICES LTD.
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NAME
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©
IPC Magazines
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Practical Wireless, May 1976
is
Edits
Any correspondence not
PCB SERVICES and not to the Editorial offices.
Post Code
be addressed
READERS
OMNI
65
04,
Peter HEMINGWAY
T
HIS device was designed as a result of reading
an article in PW some 3 years ago (Logiprobe,
by L. Cook, October 1972). The device described
Probe
there was somewhat cumbersome, and prompted me
to design a unit which was simpler, cheaper and more
compact. The fact that this device is so simple means
that it can be built into a small and very handy body,
such as a felt -tip pen or as the prototype was, built
into a discarded test probe.
Plastic housing
Circuit Details
LED's and supply
leads secured
The circuit is basically a potential divider with two
LED's to indicate the current flow through their
respective resistors. The value of the resistors
is not too critical and can be of any value from
330i1 to ikfl. However, if resistors of less than 33052
are used, damage to the LED's may result, and if
too high a value, the LED's will be too dim. As Rl
and R2 must be of the same value, they should also
be of 10% tolerance, and 18W so that they are able
to fit into the case.
The LED's used in the prototype are 5mm types,
one green to indicate logic O (or OV) and the other,
red, to indicate logic 1 (or +1V). To cut the cost
even more, .3mm diameter LED's could be used.
As previously stated the prototype was built into a
test probe of slightly smaller dimensions than a
felt-tip pen. The drawing opposite illustrates a cross
section of the unit showing the internal wiring and
components. The supply leads to the probe should be
terminated in a pair of crocodile clips in order that
the probe can be connected to the same power supply
as that used by the TTL circuitry under test.
After the probe has been tested and found to be
working satisfactorily, the wires and LED's are fixed
in place with a glue such as polystyrene cement or
+V
OV
with epoxy resin
adhesive
R
D1
_'I-
Red
D2 Green
fl
R1
330
to 1k
Probe
R2
Araldite.
330
toit
OV
D7
MLED650
Red
D2
MLED650
Green
+V
IAM0G511
Testing
A quick method of testing the probe, is to connect
the supply leads to their respective terminals of a
6V battery. If all is well, both LED's should light
at half brightness (half brightness will also be displayed when the probe is connected to a point that
is either floating or at an inadmissible voltage (e.g.
2.1V). When the probe is touched to a positive terminal, Dl (red) should light, and similarly when the
probe is touched to the OV terminal, D2 (green)
should light.
If these results are not obtained it is probably due
to the fact that one or both diodes are connected
the wrong way round.
* components list
Resistors
R1
330f2-11d)
R2
330f1-1k0
D2
MLED 650(green)
*see text.
Semiconductors
D1
MLED 650(red)
Miscellaneous
Felt -tip pen body or spare test probe. Two crocodile
clips.
Lengths of wire (two colours).
This hobby
brings big
-
rewards.
A soldering iron and a screwdriver. If you know,
how to use them, or at least know one end from
the other, you know enough to enrol in our
unique home electronics course.
This new style course will enable anyone to
have a real understanding of electronics by a
modern, practical and visual method. No previous
knowledge is required, no maths, and an
absolute minimum of theory.
You build, see and learn as, step by step, we
take you through all the fundamentals of
electronics and show you how easily the subject
can be mastered and add a new dimension not
only to your hobby but also to your earning
capacity.
All the training can he carried out in the
comfort of your own home and at your own pace.
A tutor is available to whom you can write, at
any time, for advice or help during your work. A
certificate is given at the end of every course.
'
.
it--
ì.=*
2
Build an oscilloscope.
3
O.
first stage of your training,
you actually build your own Cathode
As the
'V.
l
ray oscilloscope! This is no
FI1
understand
circuit diagrams.
short time you will be able to
read and draw circuit diagrams,
understand the very fundamentals
of television, radio, computers and
countless other electronic devices
and their servicing procedures.
In a
PLUS
ALL STUDENTS ENROLLING
IN
OUR COURSES RECEIVE A FREE
CIRCUIT BOARD ORIGINATING
FROM A COMPUTER AND CONTAINING MANY DIFFERENT
COMPONENTS THAT CAN BE
USED IN EXPERIMENTS AND
PROVIDE AN EXCELLENT
EXAMPLE OFCURRENT
ELECTRONIC PRACTICE
Practical Wireless, /Way 1976
Carry out over 40
experiments
on basic circuits.
Read, draw and
.
umatige
--:®-1/4,..
A-10,-,
toy, but a test instrument
that you will need not only for the
course's practical experiments,
but also later if you decide to
develop your knowledge and enter the
profession. It remains your property
and represents a very large saving
over buying a similar piece
of essential equipment.
FREE GIFT!
m_Y
,y
We show you how to conduct
experiments on a wide variety of
different circuits and turn the
infgrrration gained into a working
knowledge of testing, servicing and
maintaining all types of electronic
equipment, radio, t.v. etc.
To find out more about how to learn electronics in a new,
exciting and absorbing way, just clip the coupon for a free
colour brochure and full details of enrolment.
111111111011r.110111
-rMraMMMMMMMMMMMM
to:
mlomm-
Brochure without obligation
- -- --I
BRITISH NATIONAL RADIO WL56
& ELECTRONICS SCHOOL, Dept
-
Jersey, Channel Islands.
P.O. Box
156,
NAME
-_ -_
ADDRESS
-__.. ____
-
= = == === ===== --WAN Ml
-- -rareI
(Block caps please)
ION
onoow soor Nr
67
Dolby
Noise Reducer Kit
TM
PRICE: £3440 + VAT
'Wireless World'
May, June, July '75
Trademark of Dolby Laboratories Inc.
Tho latest addition to our exclusive range of matching high fidelity units.
The Dolby Noise Reduction System is designed to reduce background noise on open reel or cassette tape recorders. Used in the
signal path to and from the
tape recorder, the unit will encode (Doibyise) signals during recording, and, during playback, may be used to decode either your
own encoded material, or
commercially available Dolby encoded cassettes.
Featuring:
Typical performance
switching for both encoding (low -level h.f. compression) and decoding
a switchable f.m. stereo multiplex and bias filter
provision for decoding Dolby f.m. radio transmissions (as in USA)
no equipment needed for alignment
suitability for both open -reel and cassette tape machines
check tape switch for encoded monitoring In three -head machines
The kit includes:
-complete set of components for stereo processor
Noise reduction better than 9dB
weighted
Clipping level: 18.5dB above Dolby
level (measured at 1% third harmonic content)
Harmonic distortion 0.1% at Dolby
level (typically 0.05% over most of
band, rising to a maximum of
0.12 %)
Signal -to -noise ratio: 75dB (20Hz to
20kHz, signal at Dolby level) at
Monitor output
Dynamic Range
90dB
30mV sensitivity
-regulated power supply components
-board- mounted DIN sockets and push -button switches
-fibreglass board designed for minimum wiring
-solid mahogany cabinet, chassis, twin meters, front panel, knobs, mounting screws and nuts
Calibration tapes are available for open -reel use and for cassette (specify which) PRICE £I si + VAT.
>
S- 2020TA STEREO TUNER AMPLIFIER KIT
PRICE: £4865 + VAT
SOLIO MAHOGANY CABINET
I
A high -quality push -button FM
THD <0.1 %@20W
Tuner S/N 30dB 8 1.8µV
(mono)
Toroidal Transformer
Varicap Stereo Tuner with Interstation
mute combined with a 20W r.m.s. per
channel Stereo Amplifier.
Please add VAT at 25% unless marked thus when 8% applies
We guarantee full after sales technical and servicing facilities on all our kits
Please send SAE for complete /Isis and specifications
INTEGREX LTD.
A.S. P.
Portwood Industrial Estate, Church Greeley,'
Burton -on- Trent, Staffs DE11 9PT
Tel. Burton -on -Trent (0283) 215432. Telex 37714
TRANSFORMERS
LTD
(DEPT. PW4), SIMMONDS ROAD, WINCHEAP
CANTERBURY, KENT
Tel: (0227) 52436
CASED TRANSFORMERS
Housed in smart resin coated steel
case° with 3 core power cable
outlet socket, fused primary winding.
\
30 VOLTS
Primary 200/240V
Secondary 12, 16, 20, 24, 30V
REF. PRICE POST
-
Isolation types are fitted with 9pin
outlet sockets and are av able with
110 volt or 240 volt output
(please
p
state). Auto types
p
ypes ere fitted with 2-pin
But style sockets up to 500VA. 3-pin
sockets from 760 to 3000VA. Bee
Auto Isolation Bections for prices.
Plugs extra.
SAFETY ISOLATING
AMPS
PRICE
PRICE
REP
NO.
60
149
200
151
260
162
PLUGS
PRICE
CASED 2 Pia +Earth OPEN
£
s
s
893
098
4-70
1229
0.98'
8.81
18-81
0 98
1041
"
ij
POST
e
0.72
0.97
1.18
AUTO TRANSFORMERS
See
catalogue for full range.
VA
(Watts)
PRICE
REF.
CASED
NO.
£
93
2328
PRICE
PLUGS PRICE
a 3 pin OPEN
POST
6
19.22
L
O/A
MINIATURE & EQUIPMENT
Primary 240V with screen.
VOLTS
MILLIAMPS
Sec.
1
3-0-3
0.8
0.8
9.0.9
0.9
-
Sec. 2
0-6
0-8
0-9
Sec.
1
200
800
1000
100
890
-
REF.
Sec. 2
NO.
100
1000
238
234
212
330
& 24 VOLTS
Primary 200 -240 Volts.
full range.
PRICE
POST
8
1.68
8
0.34
0-34
0.48
0.54
0.34
166
2.12
160
13
295
1.65
AMPS
12V
/
68
24V
2
1
4
8
2
8
4
3
8.04
5.57
0.81
20
8.01
4-80
21
0.72
0.86
6
6.68
8'76
8
61
117
0.86
7.52
0.95
0.97
10
89
lÓ.27
1.18
9
REF.
NO.
71
18
70
108
a
2.47
8.07
AMPS
4.60
6-11
NO.
102
2
3
104
4
8
8
106
107
118
119
8
2.71
005
6-10
7.67
0.85
1.08
1.18
1.44
1.88
1893
18.75
17-75
80 VOLTS
Primary 200/240V
,
AMPS
0.5
00. 48. 80V
PRICE
NO.
POST
6
8
0-72
0.72
0.85
0.97
1.18
4
5
40
0.01
1022
8
8
10
12
120
121
12.10
2
3
NEW CATALOGUE 2Sp
122
189
2.51
8-76
6.85
One Amp
IiOP.LV.
100P,I.V.
200P.I.V.
800P.I.V.
7.91
090
118
1.98
1574
2010
1887
O/A
O/A
0/A
I
Price
Four amp Price
SPECIAL OFFER
ISOLATORS
0.25 100P.LV. 0.55
0.86 200P.I.V. 069
088 400P.LV. o es
0'80 BOOP.LV.
2 KVA
Fully
0.75
2 Primary windings 11screened
Secondary
115V
each (2 matching muge
Two Amp Price Six Amp Price
50PS.V.
086 50P.I.V. 0.65
100P.LV. 040 100P1.V. 0.70
200P.I.V.
045 200P.I.V. 0.80
400P.I.V.
0.60 40op.I.V. 0-90
Add 26% VAT on all prices.
NEW
NEW I
formers) 689.60 plue carriage
VAT 8%.
-- ......................
FOR
2" and 4"
PANEL METERS
Sise: ó0mm wide x 46mm
high x 40mm deep.
Movement
0-5 micro A
0- 100 micro A
0 -500 micro A
0-1 mA
0-5 mA
m,
0-100 mA
0-600 mA
0-1 Amp
0-2 Amp
0-25 Volt
0-50 Volt
0 -300 Volt
8
meter
8
VAT
8o
4"
2"
o-16ó
REF.
8%
BRIDGE RECTIFIERS
6
0.61
5.80
105
B
0-62
0.72
0.85
0.68
50 VOLTS
Primary 200/240V
Secondary 19,25,33,40,5OV
REF. PRICE POST
124
126
127
125
128
catalogue for full range.
PRICE
POST
E
70
1
12
See
112
6
9
4
10
See catalogue for
NO.
1
0.5
2
£
0 95
0.6
*,
o
Seecatalogue
full range.
Prim. 120/2401'. Sec. 120 /240V. Centre Tep with screen.
VA
Access
Barclaycard
I.R.
Owns
1260
580
170
170
170
O.0
0.5
0.5
0.5
0.6
16K
605:
8008
170
Size:
110mm
wide x
82mm high x 43mm deep
Movement
0-60 micro A
0- 100 micro A
0 -600 micro A
0 -1
mA
0-5 mA
ááó
I.R.
Ohms
1400
730
200
200
200
0.65
0 -100 mA
0-500 mA
0.1 Amp
0-2 Amp
0-25 Volt
0-50 Volt
0-300 Volt
8" meter
05
02
0.6
0.6
15K
507í
900%
200
Vu meters are complete with detectors. Modern wide
view. Price 2" 1320 Poet 10p. Price 4" 8400 Poet 10p.
VAT 25%. Lamps 95p per set. Plus 8% VAT.
MULTIMETERS,
INSTRUMENTS
r
RESISTORS,
ORS,
NEONS,
TOOLS,,
POWER
SUP -
PLIES,
etc.
Send
for
CataIoQ
b ue.
NEW CATALOGUE 2Sp
Practical Wireless, May 1976
r--,
D
Number
58
L
}
11
Motorola MC1312P Quadraphonic decoder
THE Motorola MC1312P and MC1313P are 14-pin
dual -in -line devices which have been especially
designed for decoding the two composite
signals from quadraphonic records into the four
separate audio channels. The matrix system used in
these devices is suitable for use with inputs encoded
on the "SQ" system which was developed by the
Columbia Broadcasting System and which is now
used by most of the large recording companies. It is
also suitable for the decoding of SQ quadraphonic
broadcast programmes, but it remains to be seen
whether such material will be transmitted in the UK.
labelled RT (for total right signal) in Fig.1, whilst
Lr is the total left hand signal. The device essentially
separates the total right hand signal into two
separate audio signals, namely the right hand front
signal (Re) at pin 11 and the right hand back signal
(RB) at pin 14. These two output signals are fed to
separate power amplifiers which feed the appropriate
C4
R1
39nF
3.6k
T
F
R5
Cl
220nF
4.3k
-#V1Are
39nF 3R3
s k--RI4
--^/--I--^^/
The MC1312P is designed for home entertainment
applications and introduces less harmonic distortion,
typically 0.1 %, than the MC1313P, typically 0.25 %.
The MC1313P is intended for use in quadraphonic
vehicle systems where it provides an excellent performance at supply voltages as low as 8V.
The MC1312P has a higher typical input impedance,
3Mí1, than the MC1313P, 1.8Má1. In addition, the
MC1312P can provide outputs of up to at least 2V
RMS whilst the MC1313P provides at least 0.8V
RMS before the total harmonic distortion rises to 1 %.
The MC1313P has the advantage that it can operate
in a cold vehicle at temperatures down to -40 °C
whilst the MC1312P characteristics are specified
down to 0 °C. The MC1312P has a lower signal to
noise ratio, 80dB, with the input shorted, as opposed
to 74dB for the MC1313P under certain conditions.
¡'-
43k
13
yC9
50nF
12
10
11
Top
MC1312P
view
or MC1313P
5
LF
LB
output
output
220nF
R2
..1.
C2
39nF
7
R6
43k
'
161-vv
3;6k
6
u u
u
A typical circuit for the use of either of these
devices is shown in Fig.1. It is recommended that the
component values shown should have a tolerance of
± 5% for optimum performance in this circuit. The
RT
input
n n
rti
14
-4/tr
Positive RF
supply output
RB
output
TYPICAL CIRCUIT
absolute maximum permissible power supply voltage
is 25V, but the MC1312P is usually operated from a
AV supply and the MC1313P from a 12V vehicle
supply. The current consumption of the MC1312P is
in the range 11 to 21mA and that of the MC1313P
6.5 to 12.5mA at their respective normal operating
voltages.
The SQ encoded right hand channel signal is
C5
C3
THE TWO DEVICES
Practical Wireless, May 1976
W
¡VVr
LT
input
39nF
aII-
C10
50nF
1W1791
-.AIC8
6.8nF
Fig. 1: Typical circuit utilizing the MC1312P or MC1313P. The devices
are similar In application except for the supply voltage which is about
20V for the former and 12V for the latter.
69
loudspeakers. Similarly, the total left hand signal is
separated to produce two audio output signals at
pin 2 (LB) and at pin 3 (LB). The impedance at each
of the four outputs is typically 5kfl.
The two output voltages are about the same as the
input voltage for that side, the tolerance in the signal
amplitude ratios LB/LB and RF /RT being ±1dB. The
balance between the two forward Channels also has
a tolerance of ±1dB. The amplitudes of the output
signals to the two rear amplifiers are at a level of
typically -3dB relative to those to the two front
amplifiers.
Internally these devices contain two preatmplifiers
which are respectively fed with the input RT and LT
signals via the blocking capacitors C9 and C10. These
preamplifiers each feed two "all pass" networks,
shown in Fig.1, which produce phase shifts of 90°
without amplitude variations. Each phase shifted
signal is fed into an internal resistor matrix together
with the original output from the preamplifier, the
two outputs from each matrix forming the required
front and back signals.
It is generally desirable to enhance the centre
front and the centre back separation. This is effected
by connecting a resistor between pins 2 and 11 (front
outputs) and between pins 3 and 14 (back outputs).
For 10% front channel blending, a 47kil resistor may
be connected between pins 2 and 11 and for 40%
back channel blending a 7.5kil resistor between
pins 3 and 14.
The devices are readily available from advertisers
in this magazine.
IN THE
MAY ISSUE
DIRECT- READING CAPACITANCE METER
This simple battery -powered design, based on the use
of an NE555 timer i.c., gives direct indication of
capacitance values from a few picofarads up to 104F.
A d.c. test voltage is used, allowing the measurement
of polarised capacitors and the capacitance of reverse biased semiconductor junctions.
SERVICING THE TANDBERG CTV2 -2 CHASSIS
The Tandberg CTV2-2 chassis is in many ways typical
of the latest generation of large- screen, 110' deflection
continental colour receivers, with a switch -mode power
supply and making extensive use of i.c.s. W. S. J. Brice
decribes the various faults he has encountered.
AERIAL PERFORMANCE
Roger Bunney and Ian Beckett have been investigating
the relative performance of various well -known u.h.f.
aerials. Their results form an interesting follow -up to
Pat Hawker's recent articles.
SMALL PICTURE AND RELATED FAULTS
NOW HEAR THIS!
TAPE HEADS FROM ONLY
FIELD TB CIRCUIT FOR THE PIL TUBE
Recent solid -state chassis use a wide variety of field
timebase circuits. As an example of some of the latest
techniques S. George investigates the circuit used in
the Korting 55636 chassis, which is fitted with a PIL
colour tube.
Fit a brand new head
and transform the
quality of your tape
player. Large production runs of our
standard cassette and cartridge heads
for European & U.S. manufacturers
enable us to offer single items at
bulk -order discount prices.
WHICH PATTERN?
E. Trundle's test equipment survey next takes a look at
the various patterns available to the service engineer.
PLUS ALL THE REGULAR FEATURES
NDWpost THIS!
--
0
50p Mono Cassette
Oty
60p Stereo 8 Cartridge
Oty
£1.25 Stereo Cassette
Olr
I
enclose cheque/P.O. in
NAM[
ADDarSì
0
Lack of height, bottom cramping and other forms of non linearity, and field sync problems are common faults
with older TV sets. John Law provides a comprehensive
guide to the causes of such faults.
TO
(Name of Newsagent)
MAY issue of TELEVISION
(40p), on sale April 20th, and continue every month until
further notice.
P /ease reserve /deliver the
SAVE MONEY A IMPROVE
PERFORMANCE! Fantastic
- they fit most tape players
Data sheets on full rangea
I U
full payment for Oty. marked above. All prices incl. P &P.
U
value
A.
NAME
ADDRESS
Money back if not satisfied
MAGNETIC COMPONENTS LTD Penryn, Cornwall TRIO 8AR n
MON
70
MN
IMONI
Practical Wireless, May 1976
ELECTROflK DKITAL CLOCK
with alarm and snooze feQIUII*I
Features:
5 MINUTE REPEATING,
24 HOUR ALARM
VARIABLE INTENSITY
0.7 INCH HIGH DIGITS
PULSING SECOND
INDICATOR
INDICATOR
SNOOZE
SET
ALARM
ALARM
SNOOZE
TILT OPERATION
ALARM CANCEL FEATURES
POWER INTERRUPT INDICATOR
INDICATOR
A.M. P.M. INDICATOR
ALARM TONE OUTPUT
-
Size: 130mm
x
90mm x 95mm; Weight: 10oz
;
Power supply: 230 VAC ± 10% 50Hz
Manufactured to high standards by a major American electronics corporation this superbly styled
solid-state timepiece is made available to all readers fully guaranteed.
SPECIAL OFFER
£12.48
+
TM
99
Mail order customers:
Please enclose 55 pence for postage
and packing.
pence VAT
TIME MICROELECTRONICS
WATERIDGE ROAD, BASINGSTOKE, HANTS, RG21 2RA
PHONE (0256) 66961
33,
Please send
TRIAL IN YOUR HOME. TRY OUT THE CLOCK IN YOUR HOME.
DIGITAL TIME IS NOT FOR YOU RETURN IT IN ORIGINAL CONDITION
WITHIN 10 DAYS AND WE'LL REFUND YOUR MONEY WITHOUT
I
FREE
IF
QUESTION.
I
1
electronic clocks as illustrated
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Practical Wireless, May 1976
71
Wire Wound Resistors. Our selection
of mixed valves. 30 for £1 40. 100 for
£3 50.
Audio Amplifier Module. Mullard
LP1173. Output
nominal 10 watt.
Supply vo tage +24ví, With data and
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Variicao Control Selector.
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tional and Government Departments.
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ISSUE
1976
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7
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Modiel 335'. All transistor. Med LW.
FM. 3 watts per channel S M. With
connection data. Less tuning scale.
£1800. IP P free.
Ferguson Stereogram Chassis.
MW. LW. FM. With tuoimg scale (5 +5
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P,P free.
Copper Clad Laminate. 8" x 7 " -3
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value: 0.01, 0022, 0047, 0:1,
MULTIMETER U4323
22
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34
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TYPE
U4341
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lac -0.3. 300mA in 4 ranges.
MP
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PRICE £1210 net P. A P. 75p
Takeo either
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MULTIMETER U4313
ranges. Knife edge with mirror scale.
20,0000 /Volt, High accuracy, mVdc-75rnV.
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Vac-1.5-600V In 9 rangea.
Idc-60 -120 mlcroampa In 2.
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lac
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db scale -10 to
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33
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Size -11S x 215 x 90mm.
Complete with carrying case.
test leads and battery.
U4313
(P.W.), LEIGHTON ELECTRONICS CENTRE
59 North Street, Leighton Buzzard, LU7 7EG.
2316
LES
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rd -.,
nie,l) or
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Fitted stereo cartridge. P146 £11.00.
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COLOUR GREY
-
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21"
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BSR Sincle Play Decks with Cue
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el-
9 ranges.
ranges.
Idc -006 -3A in 6 ranges.
lac-0.3 -3A In 5 ranges.
Rea)stance- 250 -5M0 In 5 ranges.
Accuracy -dc and R-21% of F.S.D.
ac and db-4% of F.S.D.
Size -167 x 98 o 63mm.
Supplied complete with storage case,
test leads, apare diode and battery.
PRICE £11.72 net P. A P. 75p.
Decca MS2400. Brand new and boxed.
-d
agfam supplied. £3 00.
Thorn T.V. 1F. Chassis 950 Series
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Metres..
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LI
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Circuit
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.a
MULTIMETER U4324
Ranges. High sensitivity. 20,0000 /Volt.
Vac-3-900V in
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tuner (NSF Telefunken), as used on
x
08"
1
35p each.
54"
74"
FULL SPEC LED
SEVEN SEGMENT DISPLAYS
4
OSCILLATOR -1 KHz and
485KHz (A.M.) at approx. 1 Volt.
Size-160 x97 x40mm.
Supplied complete with carrying
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PRICE 19.95 net P. A P. 75p
°
72
Ranges plus AF/IF Oscillator 20,00011/Volt.
Vdc- 0'5 -1000V in 7 ranges
Vac- 2.5-1000V in 6 ranges
Idc -O05 -500mA in 5 ranges
100K Logt; Meg Log; 25K Lin; 25K Log;
10Ki10OK Log; 10OK16OK Log; 50K
x
-69
PLASTIC BOXES
B. H. COMPONENT FACTORS LTD.
Coil Formers. 50 mixec. L1 25.
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x
100
of each
2 of 0.47,
(Prices Include post & packing) 10E12 -W or
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for 65p.
74"
21" 75p. 11'
ECONOMY QUALITY LCD's
MIXED BAGS ALL COLOURS OF ALL BIEEBIDEAL FOR EXPERIMENTS
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5
5 %)
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11.20
£f N net.
SPECIAL RESISTOR KITS (CARBON FILM
it
65p. 16" x 74"
85p. + 8%.
60.75
61-20
11.20
ORANGE. 11-20
0.01 uF,
32 32;32g.F, 325v. 2' x
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20005F 50v 21" x 1" 25p; 2000ttF 35v
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20p. 4500 /`960/9001,F 30y 9 #" x 14" 50p;
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11" x 4" t.p; 4,0000F 25v'3" x 11" 40p;
32uF 450v 14" x 1" 30p;; 8 -uF 16uF 450v
x ; " 30p; 1000uF 12v 11" x 4' 15p
50001 -F 53v 2" x 11" 50p; 150;200 2004F
300v 3' x 12" 50p; 16/16,16,F 350v 2" x
1" 30p; 50 /l5otrF 500v .3f" x 1" 50p;
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Try our parcel of small capacitors 20
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Aluminium Chassis.
0.220,
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2075
1120
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Electrolytics.
500
LIN
-16" lens
1075
(:KEEN 1120
YELLOW 120
net
C296 Kit -Tubular polyester, 400V, 5 of each value
0.01, 0.022, 0.047, 0.1, 0.224F, 2 of 0.474F, £2.67
net.
Ceramic Kit- square plaque, 50V S of each value,
14F,
TT45 46. 47. 49. 53. 203 each.
Crystals HIC6U. (MHz) 12700; 12891 -6;
9455 55;
9530 55; 9037.5; 9456-25;
52.01667`,;!52.02500; 37.7825; 51.56667;
52 03333); 9090-62; 963194; 9533-33,
50p eacl.
Transfilter. 455KC. AM. 5 for £1 -00.
Log
data
a
*
1223' lens
RED
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C280 Kit -PC Mounting polyester 250V
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Repanco Transformers. AF1. AF2.
1.0
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MICHAEL WILLIAMS
ELECTRONICS
Vicarage Avenue,
Cheadle Hulme, Cheshire SK8 7JP
47
Practical Wireless, May 1976
by Eric Dowdeswell G4AR
IT has always amazed me to realise that the act of
sitting down and taking a written examination,
successfully, should enable anyone to go on the
air with 150 watts DC input, or the equivalent in SSB,
without ever having touched a piece of radio equipment in their life! The results of the misuse of
such a transmitter on the neighbouring TV's are not
hard to imagine! Even if the transmission is `clean'
and up to the standards required by the Home Office
the newcomer will not have the faintest idea on how
to tackle TVI problems. Unfortunately, it is only
after the `black box' has been bought, at some expense, that these troubles come to light, which
accounts for the number of commercial transceivers
one sees for sale in our magazines, by newly licensed
amateurs. And some other hobby gets another newcomer!
But it is no good carping about the problem if one
is not prepared to suggest an alternative. The answer
must be to return to the days when one could start
with an `artificial aerial' licence enabling experiments with transmitters to be made on a dummy
load, followed by a minimum period on CW only
with low power, say 25 watts and then on to the full
licence. In this way a tremendous amount of experience can be gained and, above all, interest is
continuously stimulated. Now, pushing buttons on
the `black box' soon palls, because one is learning
precisely nothing other than the procedure of talking
to another amateur and that's just as simple as
talking on the telephone!
Nothing new in all this of course, so what's the
snag? Just that the licensing authority would not be
prepared to undertake the additional work involved.
But in the interests of amateur radio could not the
RSGB undertake to administer such a scheme? With
official approval, of course, with the Home Office
just issuing the bits of paper. Oh, well, just a
thought!
Stephen Budd A8713 of Worthing reckons that
since the sunspot numbers seem pretty constant now
we could be at the bottom of the cycle so he's looking
forward to better times. Well, I think we have been
at the bottom for some time and in spite of the fact
that new spots have already been seen for the new
cycle it will be a year or so before any significant
Practical Wireless, May 1976
improvement is noticeable. Paul Turner in Bishops
Stortford turned his spell in bed with flu to good
use by extending his aerial and putting his new
QR666 close to hand. He likes this Trio model except
that he feels he'd like a higher ratio drive on the
bandspread to assist with resolving SSB on the higher
frequency bands.
Now for the good news! Jeremy Hinton of Newcastle, Staffs., is now ex- A8962, thank goodness, and
proud owner of G8LIZ for the moment but could
have his G4 +3 by this time, as he was about to take
his Morse test any day. He couldn't wait to get on
the air and so popped round to G8KTW's shack for
a quick QSO with his new call.
Plenty of useful info in the latest Bulletin from
Stew Perry W1BB for the 160m addicts. Like W8LRL
who made WAC in two hours in the CQ 160m competition in January! As Stew says, `WOW'! Seems
OK1ATP write about his 160m beam in the Oct 75
QST. Anyone have any info on this? Depends whether
it goes up or outwards before I could try it out!
Stew worked EA8CR /9 for his No. 127 country on
the band. Paul Barker in Sunderland zoomed in on
the SSTV contest but bad conditions limited his
results in Europe. The ARRL contest the same weekend didn't help either as no-one seemed to respect
the accepted SSTV frequencies.
Peter Readings, not too far away from me, in
Woking, was taken by my remarks on newcomers to
amateur radio, in the March issue. He started in
1935 with a one -valve PW design for the short waves
and getting back again now is brushing up for the
RAE, in due course. Martin Chapple A9090 in
Leamington Spa writes in for the first time. Aged 14,
he was `converted', as he puts it, to amateur radio
when he visited a local special events amateur
station. He progressed rapidly to a Trio 9R59DS and
a 100ft wire and now contemplates a Microwave
Module for 2m and 8- element yagi plus the same
again for 70cm. He queries the many odd prefixes
to be heard these days. The best way to find out
where they are is to look at the ITU block allocations rather than the usual prefix list, which is
obviously going to be out of date the moment it is
printed. R. Berry of Colne thought he was interested
in the VHF bands until he got his 9R59DS going on
20m and now has the DX bug. He heard TG9TI
helping in the earthquake disaster which hit
Guatemala.
Alan Doherty in Portrush, Co. Antrim found plenty
on 80m in the early hours with 3D2KG pushing his
total of countries heard on that band to 172. He
has an FR400SDX and FR5OB for keeping an ear on
two bands at once! I wouldn't mind the FR400SDX by
itself! His inverted -V on 80m is likely to be changed
to a delta loop before long. More info, please! Peter
73
Allen A8677 was pleased with the improved results
from using a 132ft wire and found ZL3NR /C on 80m,
which can't be bad!
A most interesting letter from Jim Durrant G4CEX
of Solihull, in which he supports my views on the
lack of encouragement being offered to the newcomer by the RSGB. He plodded on alone "the only
English book I found of help was the one by Frank
Rayer" (well-known. PW contributor). "When I got
my ticket I joined the RSGB automatically but gave
them up after a couple of years as a bad job
.
don't think I have seen one article in Radcom that
would be of any use to a beginner ". Need I say
more? He. continues "I wish the powers-that-be in
the RSGB would take notice of your remarks and
really do something for the novice!" Congrats Jim
on sticking to it and I know you will not regret
getting your ticket, in spite of the obstacles.
A letter in a similar vein from A. J. Lees of
Bournemouth, copy to the RSGB, says he always
recommends beginners to take PW "as this magazine has done more for beginners than any other
magazine ". He says "the newcomer eagerly scans
Radcom to no avail and becomes disillusioned and
thinks he has wasted his money". If you are listening
regularly how about some reports OM ?? Alan Dixon
A9037 of Kingston sympathises with Steve Cottis who
had trouble getting on an RAE course. Alan was
only 14 when he started his course last September
and has just heard that he has passed his RAE in
...
the December exam! Fantastic! So cheer up, Steve,
it can be done.
Finally, a note from Les Light G3KDL, Hon. Sec.
of the Radio Society of Harrow, club calls G3EFX
and GBJMR. Meetings every Friday at 8pm at the
Harrow Sea Cadets HQ, Woodlands Road, Harrow.
Features during April are a debate on HF and VHF
propagation and a talk on mobile operation by Fred
Barnes G3AGP. Two evenings a month are kept for
practical work and construction. So flock along folks,
nothing to lose but your bus fare!
I have been asked to dispose of a Hallicrafters
S108 receiver. Valves, thank goodness, MW to
to 32MHz continuous, with amateur bands 10 to
80m on main dial, BFO, noise limiter and excellent
manual. Condition is very good and has been checked
out by yours truly. Sorry, but must be inspect and
collect, which a buyer would probably prefer anyway!
Log extracts
S. Budd:- 80m A4XGC CO2JA
C31LC EA9FC
FG7AR /FS7 HZ1SH PJOUSA OE6DK /YK ZL3GG
ZL3NR /C 9Y4NP 40m VK3ZL 6W8FP 15m A4XGC
ZD8AR 9V1SH 20m FG7AR /FS7 ST2SA (14250 0700
Fridays) VS6BL YB1HF 9N1MM
P. Barker:- 20m SSTV CT1JI F9XY I1SU IOPCB
OZ5FG SM5EEP 20m A6XP EA8CR /9 OE6DK /YK
OE7XBI (Olympic Games, Innsbruck)
A. Doherty:- 80m EA8CR /9 FL8DJ HK1CHL
HP3XWB HR3JJR KL7HFQ PJ8C0 VP2DQ 574LW
3D2KG 20m YN7NHW
P. Allen:- 80m WB9AJF /6Y5 ZL3NR /C 15m
TU2EI 5N2ESH OE6DK /YK (Golan Heights) C9MJ0
(Mozambique) 3B8CV
All stations are SSB except those of P. Barker, all
SSTV.
of the signal, ten minutes verbatim of the pro-
SHORT WAVE BROADCASTS
by Derek Bell
"defector ", if I may call him that, from the
ranks of the licensed amateurs is Allan Bing
G4BKM of London who forwards a sample of
the duplicated report forms he sends out in search
of QSL cards. These forms give all the relevant
information in neatly spaced sections with the largest
space devoted to the ten minutes of programme
content that stations usually require. Despite this,
Allan complains that Radio Pakistan turned down
a request and on checking the tape recording of
the broadcast all details were found to be correct.
It seems to me to be a case of the station log being
at fault!
Two more newcomers to the hobby ask questions
that I must deal with in two sections, A. B. Towler
of Newcastle on Tyne would like to know what to
put into reception reports to gain QSL cards. This
should comprise the following: time in GMT,
frequency, your set and aerial type, the SINPO rating
74
gramme content and your name and address. It
also helps to say a few kind words and say "please "!
Information on types of set, aerial systems etc can
be obtained from the many very good leaflets issued
by Radio Nederland, PO Box 222, Hilversum,
Holland. I do not know of any duplicated report
forms for sale but the Post Office air letter form
should suffice provided that one does not have to
send IRCs to the station.
Sylvia Wood of Godalming is our second newcomer
although she is seeking help to get her RAE "ticket"
so we may seen loose her. Ah well! win some, lose
some! The path to this side of our hobby starts by
getting the Guide to Amateur Radio from the RSGB.
Meantime, Sylvia, you will have to be content with
joining we mere DX fanatics. The log you were
asking about is usually a tattered notebook that the
DXer keeps of the time, date, frequency and station
name in order to jog his memory or give him a
guide as to what was heard and at what time of year,
since not only does reception vary with the season
but we are now in the sunspot minimum of the
solar cycle and it will be 1978 before we can expect
the beginning of any improvement.
Midst all the gloom however, David Sewell sends
us a selection of his best and these are Latin
American stations. This aspect of our hobby attracts
many listeners who like to specialise in these
stations. since there are many differing styles and
programme content is equally varied. Look forward
Practical Wireless, May 1976
CRESCENT RADIO LTD.
I1 -15 & 17 MAYES ROAD, LONDON N22 6TL
(also) 13 SOUTH MALL, EDMONTON, N.9
MAIL ORDER DEPT.
I
ST. MICHAELS TERRACE, WOOD GREEN,
Phone 888 -4474
LONDON N22 45J
CLEAR PLASTIC PANEL METERS
Size 59mm x 46mm x 35mm these meters require a
38mm hole for mounting.
ME6 =0 to 50 micro amp Full Scale
ME7 =0 to 100 micro amp Full Scale
ME8 =0 to 500 micro amp Full Scale
ME9 =0 to 1 m/a Full Scale
=O to 5 m/a Full Scale
ME I1 =0 to 10 m/a Full Scale
Fulll Scat
ME13 =0 to 10
ME14 =0 to 100 m/a Full Scalle
ME14 =0 to 500 m/a Full Scale
ME15 =0 to 1 amp Full Scale
ME16 =0 to 50 volts
ME17 =0 to SOO volts
A.C. Full Scale
OUR PRICE
00
ME18= "B "Meter
+8
ME19 = " VU Meter
_1
Fl
WAFER SWITCHES
1 Pole
12 Way
2 Pole
2 Way
2 Pole
3 Way
4 Way
2 Pole
4 Way
Pole
4 Way
3 Pole
4 Pole
3 Way
27p each
Phu the Ferrite Aerial and switch which you connect
following our complete instructions.
Now you only need a 9.12 volt D.C. supply and you can
feed this tuner Into any Stereo Amplifier.
FANTASTIC VALUE AT 1700+25% VAT
8",,
r Ilq
pit
f
1'1'1 switched 3, 4 {, 8, 71,
9 and 12 volts at 500 m /a,
with on/off switch and
pilot light. Size: 130mm x
55mm x 75mm.
ONLY 54.00
Fes Switched 8 71 9
volt Battery Eliminator.
x 31.".
Approx. aloe 21" x
Ideal for cassette recorders
5325 PP3 Car converter.
From 12v Pos. or Neg. to
= 6 -75
volt. Easy to
fit and transistor regulated
sr
-9
13 90
A plastic box with moulded
extrusion rails for PC or
Chassis panels with metal
front plate fitted with four
screws (all supplied).
An ideal box to give a smell
finish
project a
41oi
(a profess 81mm h
(Internal)
51mm x 28mm.
OUR PRICE
+8%
40P.
MINIATURE RELAYS
Brand new range o
British made Relays. Sire
x } ". All two
I }' o
changeóvers with 250v
and eultable
contacts
1.6A
for fitting on 1m Veroboard.
Type Volts Cur- Ohms
rent
27/A
12v
8 vas.
*OUROnly 8" long and weighs just bite
are available)
PRICE 8915 +8% (apare
AMPLIFIER
Translator Stereo Ampllwith Vole, Base,
Balance and Tone Controls.
Approx. 3 watts into 8
ohm per channel needs a
9/12 volt DC supply and
is complete on a 2}"x70"
P/C board.
Ideal for domestic record
players, etc. A Bargain at
8
lier
55 +25% VAT.
Point 2
Top -efficiency in heat transfer.
Element slides inside the
soldering bit.
25 watts but equivalent in
heat capacity to 60 watts.
Point 3
High grade phenolic
handle
(own moulding!)
Stainless steel shaft.
core 0.4mm.
Flexible lead.
-3
Point 4
Just connect the input of this unit to
and 4.7mm.
sensitivity control.
-'"
e>!+!es
the loudspeaker termillets of an amplifier and our r,,, t three 250V up to
1000W lamps to the output terminals of the unit, and
produce a fascinating sound-iight display. (All
you
guaranteed.)
£18.550 plus 75p P. A P. +8%
-
BARGAIN TRANSFORMERS
12.0 -12
volt
500m /a
volt primary transformer bargain.
60mm x 40mm x 50mm
approx size
fixing centres 75mm
£.1.20 + 8%
Our Price
240
Iron -coated bits that do
not stick to the shaft but
slide on and off easily.
3 tip sizes 2.4, 3.2
Point 5
Price with standard
(3.2mm.) bit
£3.20(P +P 0.22)
Spare elements
£1.52
Spare bits
£0.50incl. V.A.T.
P.C. ETCHING KIT
This kit contains all that
the constructor will need to
etch the circuits of his own
Point 6
A well balanced
tool -
=184mm x 124mm x 60mm =51.26
1021 = 106mm x 74mm to 45mm (eloping front) =05p
design.
TELESCOPIC AERIAL
dish. Sample copper clad
length 22cm.
weight 50gr.
AB8 PLASTIC BOXES+ 8 %
Handy boxes for construction projects. Moulded
extrusion rails for P.C. or chassis panels. Fitted with
1mm front panels.
1006 =105mm x 73mm x 45 rum =559
1006 =150mm x 75mm x 47=
5p
1007
Contents-Plastic etching
Nine section fully swivelling telescopic aerial with 4BA
single bolt fixing or two hole fixing bracket.
Fully extended =43"
Fully closed =7"
Our Price 50p +P /P +VAT a) 25%
LOW NOISE LOW PRICE CASSETTES +8%
Good quality tape In well made screw type cassettes.
Presented in single plastic cases.
C80 = 33p
C90 -48p
C120 =60P
10% Discount on ten or more cassettes of one type
21" 80 oho,
o" 8 chm
Manufactured by 'FLAG" to a
very high standard these loud speakers are a real bargain
SPEC:Size =10" Dual Cone.
Power -10 Watts
Sap
verande 5125
board; Laminate Cutter;
Ferric chloride;
1
lb
Large Plastic Spoon; Etch
Resist Pen: Full Etching
Instructions.
Complete and Big Kit
Value at í3.75p +8 %
10 -INCH 8 OHM DUAL CONE
LOIIDSPEAHER8 +25%
21" 8 ohm
Sap
gpp
21" 40 ohm
i
Breakdown voltage 1500 A.C.
Leakage current 3.5 uA.
FERRIC CHLORIDE
Anhydrous ferric chloride in double sealed one pound
lb.
poly packs. Our Price 65p +P /P +VAT @ 8% per
3 KILOWATTS PSYCHEDELIC
LIGHT CONTROL UNIT
Three Channel Base
Middle, Treble, Each
channel has its own,
-
LOW VOLTAGE STEREO
17M /A 700
21 /A 12V 28M/A 430
8v
33M /A 185
12 /A
All 51 .30 each
Completely Portable
Heats in 5 seconds
Solders up to 150 joints or more per charge
Recharges automatically in Its own ,tend
No AC leakage or induced current to damage
delicate components.
Heats to 700 deg. F
Fine Tip for delicate and general purpose soldering
*
*
prices include Vat
p & p extra as shown
in brackets
Near -perfect insulation.
CABLELE88 SOLDERING IRON WAHL. "ISO -TIP"
**
**
*
Quickly
with ANTEX
Model X25
Point 1
r
+8%
SCOOP PURCHASE
MW -LW -FM STEREO TUNER
We supply a MW -LW-FM -Stereo Tuner fully
wired and aligned on a 6" o 4" x I }" printed board,
POWER SUPPLY UNITS r
BARGAIN PROJECT BOX.
Get to the Point
Frequency-40-1200011r
'
- ?5?;, Our Price - 5375p each
D.H. CARRIAGE 50p UNLESS OTHERWISE STATED
LVAT --All prices are excluding VAT. Please add to each item the VAT rate indicated.
Practical Wireless. May /97t5
STAND ST.3
High grade insulation material,
chromium plated steel spring.
Suitable for all our models.
Replaceable sponges,
space for spare bits.
Complete£1.37(P+P 0.24)
00000
Please send the
From electrical, radio or car accessory
shops or from Ante% Ltd., Freepost
(no stamp required) Plymouth.
1 BR Telephone 0752 67377/8
PL1
following:
Name
ANTEX colour catalogue. Address
---
enclose cheque /P.O. /Cash
(Giro No. 258 1000)
I
L---
-------
PVM'5!76
-J
75
CODAR
*
AERIAL
TUNER UNIT
SHORT WAVE KITS
You'll be proud to say .. .
R.Q.80
*
"1
This new CODAR A.T.U. tunes -5 -30MHz and is designed to match random
length single wire aerials from a few feet of indoor aerial to long outdoor
wires to the receiver.
Hi -Q low loss air spaced CODARCOIL Inductor with no less than IO position
tapping switch and tuned by two air spaced variable capacitors, gives exceptionally wide range of matching to all types of receivers.
Compact size, handsome low slim line cabinet 9' x 5" x 2 } ". Ready for use.
Price LI1 00 (carr. free + C275 VAT. "Well satisfied" Mr. Andrew. Devon.
I
* P.R.40
Will substantially improve receiver performance over
-5/35 MHz. Three
switched bands, Codar -coil low-loss airspaced inductor with F.E.T. and wide
band R.F. amplifier gives outstanding performance. A must for the keen S.W.L.
Price
.00 (carr. free) + 02.75 VAT. "Fantastic" Mr. A. White, Lincs.
I
ill
CODAR COIL -PACK
Complete unit 550 KHz -30 MHz in 4 switched bands. With Aerial trimmer.
Aligned, tested, ready for use. Suitable for valve or F.E.T. Mixer /Ose. As used
in the CR70A. Full instructions included for 450/470 KHz I.F.
Price L7-99 (carr. free) + CI -99 VAT. "just what I've been waiting for!"
Mr. New, Sussex.
*CR70A
Due to the very large amount of orders for the hand -built CR70A
communications receiver (UK and Export) now in hand -we regret
that we are unable to accept orders until further notice.
/BARCLAYCARD.
Quote No. clearly on Order.
)
*
Pay by ACCESS
built
NEW!!
it!"
MINI CLIPPER
T.R.F. SHORT WAVE KIT
Tunes 550 KHz -30 MHz complete coverage with 4 miniature plug -in coils.
Receives AM /CW/SSB. Electrical bandspread. Output for low impedance
headphones or any 2/8 ohm speaker (optional extras). Full step by step
pictorial instructions, simple to build, Printed circuit board. Steel cabinet.
A quality Codar -Kit, 12 month guarantee. The ideal low cost starter Kit for
the beginner S.W.L. to enjoy the fascinating hobby of long distance listening
and collection of colourful Q.S.L. cards from all parts of the world! (Size and
appearance similar to the RQ80). "Worked first time"
Mr. Short- Dudley
Price complete (less PP6 battery) £10.80 (carr. free) + L2.70 VAT.
*
R.F. PRESELECTOR
*
TELECOMMUNICATIONS AND
ELECTRONIC EQUIPMENT
MANUFACTURERS
MULTIBAND
-6
T.R.F. SHORT WAVE KIT
Tunes 550KHz -30MHz complete coverage with 4 miniature plug -in
Receives AM /CW /SSB. Separate electrical bandspread. Main tuning
brated, vernier slow motion drive. Output for any external 2/8 ohm
speaker. Headphone jack. World -wide reception. Handsome styling,
cabinet. Full pictorial instructions, easy to build, printed circuit board.
Price complete (less PP6 battery) CIE-00 (carr. free) -f- C4.50 VAT.
*
*
*
coils.
cali-
loud-
steel
CODAR AERIAL -KIT
Approx. 50' stranded copper Aerial wire, plus 25' insulated lead -in wire,
insulators, leaflet hints and tips on types of aerial.
Price L2.40 (post free) + 60p VAT.
4
FREE!!
Illustrated leaflets on request! (Stamp appreciated!)
EXPORT CUSTOMERS! We offer world wide mail order, free quote /leaflets
on request. (International Reply Coupon appreciated /)
CODAR AIR SPACED COILS -Any quantity supplied-please state dimensions required, for free quote.
JUST OUT!!
The new "Mini Clipper RB
(less PP6 battery)
with
"-readybuilt
/tested
guarantor
only E15.00
0V5 TAT! -Also Multiband RB ready buìit,tested
built/tested (less bats.)
L2900 + C6.00 VAT!
CODAR® TELECOM LTD., UNIT 2, BURRELL BUILDINGS, CHURCHILL INDUSTRIAL ESTATE, LANCING, SUSSEX. Tel: 090-63 -61901
FND500 Jumbo 0.5" CC Red LED now only £102
ADVANCED CLOCK KIT
AERIAL BOOSTERS
We make three types of Aerial
Boosters all for set top fitting, with
Co -ax Plugs and Sockets.
B11 -For Stereo and Standard
Complete kit including attractive slim case for 6 digit alarm clock with bleep
alarm, snooze, high brightness driving of Jumbo LED displays, automatic
intensity control -with optional add -ons of touch switch snooze control
and crystal control /battery back -up.
£2680
ECH84,
P.E. CAR CLOCK with Journey Timer
mon. or colour this
covers the complete UHF
band.
All Boosters are complete with
Battery and take only minutes
Colour Valves 30p each PL508,
to
P1.509, PY500 /A.
Price E3 .90 each.
"`'
Small Plastic Boxes (white) made out of high impact plastic with flick
on lids. Ideal for most protects. All three types one price. Prices 15p each.
Ten L1.30. Size (approx.): Type 1 }Ins x 2flns x lin deep. Type 23)Ins x 2 Ins x 21ns deep. Type 3 -Sjlns x 3 1Ins x gins deep.
-
digit clock for use in any car with 12V battery, with an Independent journey
timer incorporated. Bright Jumbo LED display comes on with Ignition
automatic intensity control. Complete kit of all parts needed including
case, PCB's and all components. Full instructions.
E39.50
Easy to Build E.E. DIGITAL CLOCK (Jan. Issue). Kit of all components,
including case etc., for this attractive clock with 12mm green display. Full
instructions.
E1570
6
50
Hz Xtal Timebase Kit for clocks (Intl. advanced kit above).
CMOS !CS
RCA MOT
ONLY
CD4000 0.17
CD4001
017
CD4002 0-17
CD4006 0.97
CD4007 0.17
C134008 0.79
CD4009
CD4010
CD4011
CD4012
CD4013
CD4014
CD4015
CD4016
CD4017
CD4018
CD4019
CD4020
0.46
0.46
0.17
0-17
0.48
0.83
0.83
0.46
043
CD4029 0.94
CD4030 0.46
CD4031 1.82
CD4032 0.68
CD4033 1.14
CD4034 1.56
CD4035 0.97
CD4036 1.82
CD4037 0.78
CD4038 038
CD4039 2.66
CD4040 0.68
CD4041 0.69
CD4042 0.69
CD4043 0.63
CD4044 1.77
CD4045 1.15
CD4046 1.10
r
CD4059 3.64
CD4060 0.82
CD4061 16-43
CD4062 7-33
CD4063 0.90
C134066 0.58
CD4067 2.95
CD4068 0.18
CD4069 0.18
CD4070 0.18
CD4071
0.18
CD4072
CD4073
CD4075
CD4076
CD4077
CD4078
0.18
0-18
0.18
127
0.18
0.18
CD4081 0.18
CD4082 0.18
CD4510
CD4511
Displays
1-12
1ß8 5LT -01
2.56
CD4514
2-56
CD4515
1.12
CD4516
CD4518 1.03
CD4520 1.03
CD4527 1.30
1.16
CD4532
0.74
CD4555
C04556 0-74
MC14528 086
MC14534 6.04
MC14553 4.07
MC14566 121
MCM14552
DL704E
FND500
5.80
0.75
1.02
Display Int.
SN75491
S N75492
CA3130
for 830
IOWAY 1M
10M
Clock Chips
3
Prices Include V.A.T. P. A P. under £1.15p, £1 to £3-20p above £330p.
Overseas at cost. Money back guarantee on all orders.
62
ELECTRONIC MAILORDER LTD.,
BRIDGE ST., RAMSBOTTOM, BURY, LANCS. Tel. Rams.
0.60
4.80
IC Sacket
IC)J(Lf
CJ
I-
LTD. P.O. BOX 34,CANTERBURY,CT1 1YT
ANTEX SOLDERING IRONS
(with slide on 8 off bits)
15W
'C' miniature irons
SINTEL, 53n
ST3 Stands -for all modela
SOLDER in Bib dispenser
17
Official orders welcomed (wr tten or phoned)- Univs, Polys, Govt, Cos, etc'
Export orders: no VAT, add 35p (Europe) £1 (oversees) for Airmail p & p.
(No Export outside Europe for databooks and transformers).
Aston Street, Oxford. Tel:
3036
AU. PRICES INCLUDE P&P AND V.A.T.
3/32'; 1/873/16"bits-each
'C Elements
18W 'G' miniature irons
3 /3271 /873/16 "blts -each
'G' Elements
15W' CCN'Low leakage irons
3/3271/8(3/16" bits -each
'CCN' Elements
25W 'X25' Low leakage Irons
3 /3271 /873/16 "bits -each
'X25' Elements
C134047
ITV Channels.
B45 -For
1.02
0-88
1.00
fer
VHF Radio.
612 -For the older VHF Television, please state BBC1 and
PCF802, PCL82, PCL84, PCL85,
PCL805, PCL86,
PFL200, P1.38,
PL504, PY33, PY81, PY800, PY88,
EH90, 30FLI, 30FL2, 30PL14, 6F28
0-01
Flat Cable
20WAY 1M
8.05 10M
ECC82,
ECL80,
EF80,
EF183, EF184, PC86, PC88, PCF80,
0.74
MK50253 5.60 Pins
CD4048 0.46 C134085 0.59 MM5314 4.44 1.00
0.50
CD4049 0.48 CD4086 0.59 AY51224 3.68 '000
4.00
CD4050 0.46 CD4089
AY51202 4.76 3000
1030
CD4051 0-77 CD4093 0.66 MK50250 5.00
CD4023 0.17 CD4052 0.77 CD4094 1.53 CMOS
Verocases
CD4024 0.64 C04053 0.77 CD4095 0.06 Books
751410J 2.64
C134025 0 17 CD4054 0-95
CD4090 0-$6 No VAT or
7514110 2.94
CD4026 1.42 C04055 1.08 CD4097 2.95 P A P
751412K
4.00
CD4027 0.46 CD4056 1.08 CD4099 130 RCA1975 2.67 uA78L12WC
CD4028 0.74 CD4057 20-35 CD4502 0.98 MCMOS 2.77
9.80
ADD VAT at 8% (Higher ate does not apply to any of above).
15p P 6 P on orders under £3- Despatch Is by 1st Class Post.
Price list and data sent FREE with an order, or on request (an SAE helps)
0.83
0.46
0.92
CD4021 0.83
CD4022 0.79
76
VALVE BARGAINS
Any 5-64p, 10- £1.10, S0 -£5. Your
choice from the following list:
0965 49791
'SKI: 'SK2 :Soidering Kits
£2.30
£0.45
£1.10
£2.50
£0.45
£1.35
£2.70
£0.45
£1.50
£2.30
£0.47
£1.15
£3.85
£1.10
£0.45
WIRE STRIPPER 8, CUTTER £0.85
HAND DRILLS Leytool precision,
compact ,5/16" chuck
£3.99
AERIALS Extend 15 -120cm £1.50
CASSETTE ' Heed Demagnetisers'
Shaped pole -saves time
£3.65
EARPHONES Stethoscope £1.25
Crystal earphone, lead &plug £0.65
Headphone, 2,000 n.
£3.20
INTERCOMS 2- station
£6.35
Dynamic
£2.15
MICROPHONES
PRINTED CIRCUIT KITS -AII
items for producing p c'e £3.99
SIGNAL INJECTOR -Audio through
video signals, self contained £4.25
STEREO HEADPHONES 8rs £4.85
SPEAKERS -75mm dia.9t £1.00
Practical Wireless, May 1976
to Lara Venezuela on 4800 at 0220, Juventud
Venezuela on 4900 at 0050, Barquisimeto Venezuela
on 4990 at 0135. These were all pulled in on Dave's
Trio 9R59DS with a trap dipole 25 feet high, but all
the same, undoubtedly and verily, only for night -
owls!
Ian Walker of Crouch End, London is baffled by
station he heard on 2300 and 2750 simultaneously.
This came in on Ian's Sony ICF5500M via the set's
telescopic aerial. The clue to the ident of this
station is its claim to be "The voice of Soviet public
opinion "! The station is Radio Peace and Progress
and very little is known of its staff or its aims for
that matter. Ian describes the programme content
as documentary on political topics.
Just a short while ago the latest edition of the
Radio RSA bulletin plopped on to the mat at chez
Bell. This leaflet, a mere shadow of its former self,
covers the period of the summer schedules starting
in March and indicates that RSA will use 5980, 7270,
11900, 11970, 17780, 15155, 15220 and 21535kHz. Their
signals are radiated, with short breaks, twenty four
hours a day to various target areas and in different
tongues, but, strangely, while they have English
transmissions they only specify North America as
an English target area while the other area is just
designated "Europe".
Robin Bayley of Kingswood School, Wolverhampton reports the 15155 RSA service in German
at 1800, on a Marconi R1475 with a long wire, plus
NHK Tokyo on 15430 at 0805, TWR Bonaire on 11920
at 0030, Radio Nacional de Brazil on 11780 at 2100.
Another youngster is Stewart Fenwick of Clacka
mannan in Scotland, who reports that Radio Pyongyang recently sent him a QSL after 106 days and 1
use this to mention that reports have been noticed
of late that the station in Fukien, China has reemerged after a long period, on 2430. This station
is very rarely reported and I can remember at a
European DX Council conference a German DXer
showing me one of their QSLs, written on rice paper
in Chinese, which he had waited a donkeys age to
get. At this time he claimed the station was a small
transmitter working mobile so if any one chances
on them please let us know all the details.
Ken Smith of Ross-on -Wye has some enquiries to
make about the Voice of America transmitter at
Rhodes. He thinks that the frequency has changed
for the 2100 session and asks for any information of
new frequencies. As I have said above, it is about
this time of year that the schedules change and so
it is possible that this station has disappeared from
its usual part of the spectrum. A reader who just
wants to be known as "SS" suggests that the Radio
Australia signal on 9745 mentioned recently, in fact
comes from Melbourne as he monitored it over
Christmas. This may well be since stations, through
many causes, have to depart from the published
schedules and the poor old scribe slaving over a
hot tripe -writer can only rely on his friends who
write in to keep him up to date. SS also craves
info on "what to do with aerials ", well, one thing not
to do is to fasten them rigidly to trees, since, as
happened to a friend of mine in the recent gales,
the tree swayed and down came the lot! The answer
to this is to secure the long wire with one of those
rubber "ropes" that are used on motor cycle panniers
and car roof racks. If it is an inverted "L" longwire
have the foot of the "L" running down from the
support post and not down the house wall, and feed
into the house via a wire run from the far end of
the aerial. That brings this session to a close so I
will wish you and yours best 73s.
the network, in addition to CKVO, are CHCM in
Marystown on 560kHz, CKCM in Grand Falls on
620kHz, CKGA in Gander on 730kHz and CKIM Baie
Vert on 1240kHz, all of which have been heard
recently in the UK. VOCM is one of the few medium
wave stations in Canada to use the prefix V in its
callsign; the majority start with the letter C.
Newfoundland became the 10th province of Canada
in 1949 but VOCM and four other well established
broadcasters managed to hold on to their original
call letters that were issued when the territory was
still a Crown colony.
The World Radio and TV Handbook, generally
regarded as the DXers 'bible' is published annually
in Denmark and distributed in the UK by Billboard
Publications. It is printed in English and can be
ordered through bookshops. It costs £5. The WRTVH
lists all known broadcasting stations ( and TV
stations) with the exception of low power locals in
the USA and low power relays elsewhere. AM
broadcasting stations are listed by frequency and
there is a section for each country which gives the
hours of transmission, addresses and QSI, information. The less pretentious "Guide to Broadcasting
Stations" at 80p is produced in the UK by Butterworth and is on sale in many bookshops. AM
broadcasters in Europe and North Africa are listed
along with a selection of the more powerful medium
wave transmissions from other parts of the world.
.
MEDIUM WAVE DX
by CHARLES MOLLOY
THIS MONTH Alan Crookes reports from his
new QTH in Sheffield. He had to rebuild his
loop after moving house but his 'shack' is now
fully operational and he is using a Murphy B40A
communications receiver to pull-in his medium wave
DX. Stations logged include WINS, the all-news
station in New York City, which transmits on
1010kHz with a power of 50kW and three locals in
Newfoundland, CBN in St John's on 640kHz, CKVO
in Clarenville on 710kHz and CJON St John's on
930kHz. Alan points out that the announcement
"VOCM Radio Service" from CKVO is misleading
since CKVO is not mentioned in many station
listings, including the 1975 World Radio and TV
Handbook, as it came on the air as recently as
December 1974. The VOCM Radio Service is a local
network in Newfoundland with VOCM on 590kHz
in St John's as the key station. Other members of
Practical Wireless, May 1976
77
North West England, can hear Connemara
during the evening after dark, using a Marconi
Mercury receiver and a medium wave loop. The
station is on the air from 1800 to 2100 approximately
and with a bit of luck might just be audible in the
London area. Radio na Gaeltachta is an example
where DX means Difficult rather than Distant.
Torshavn in the Faroe Islands on 584kHz is another
`Difficult' station. Some DXers, including the writer,
have had to wait for years before receiving a rather
attractive QSL card as a reward for persistance.
D. R. Mayhew reports hearing Kinshasa in Zaire
on 692kHz and Dakar in Senegal on 764kHz, using
a Philips receiver and medium wave loop aerial.
Medium wave stations in Africa are often heard well
in the UK at this time of year. A loop is very
useful for listening to this continent since the DX
lies to the south and the interference from Europe,
in general, comes from the east so it is not difficult
to null -out the QRM. Stations to look for during the
evening are Tenerife in the Canary Islands which
broadcasts in Spanish on 620kHz; ELBC in Monrovia,
Liberia which has English programming on 629kHz;
Enugu, Nigeria which is a weak signal clear of interference on 1320kHz at 2300; Nouakchott, Mauretania on 1349kHz and, from the Republic of Guinea,
Conakry which is a strong signal on 1403kHz after
2300hrs. There are two long wave stations in Africa,
both coming in at good strength in the UK. From
the top of a mountain near Azilal in Morocco the
home service in Arabic is transmitted with 800kW
on 209kHz, while from nearby Algeria the French
programme comes from Tipaza with a power of
in
This is a very useful book for the beginner. A
similar publication "World Radio TV Listings" is
available for 60p.
The Foreign Broadcasting Information Service of
the United States Government produces `Broadcasting Stations of the World Part 2" at intervals of
about two years All broadcasting stations locat"(l
outside the United States and in the frequency
range 150kHz to 26MHz are listed. This bulky paperback can be obtained for $2.50 postpaid from the
Superintendant of Documents, Government Printing
Office, Washington,
DC 20402,
USA.
Quote
Pr.Ex- 7.9:972 Part 2 and be prepared for a wait of
several weeks!
Steve Whitt (London) refers to a wavetrap which
he inserted between his loop aerial and the input to
his communications receiver, in order to reduce
local interference on 1546kHz. It is a parrallel tuned
circuit which can be tuned across the medium wave
band. It offers a high impedance at its resonant
frequency and a low impedance at all others and
when it is placed in series with the aerial lead, it
will reduce the strength of an unwanted station,
leaving others unaffected. A medium wave tuning
coil and appropriate variable capacitor, or pre -set, to
tune across the medium wave band, are the only
components required. The coupling winding is not
used. Tune the receiver to the unwanted signal,
adjust the wavetrap for minimum signal strength and
the receiver can be used normally.
S. Lydon (Kingston-on- Thames) has been trying,
without success, to 'tune-in to the Irish Speaking
Radio (Radio na Gaeltachta), a network of VHF and
MW transmitters in the Republic of Ireland. There
are three outlets on the medium waves; Connemara
on 539kHz with a power of 2kW, Kerry on 962kHz
with IkW and Donegal on 1250kHz with 10kW. In
spite of their proximity to England these- stations
are rather difficult to pick -up, mainly on account of
co- channel interference. The writer, from his QTH
Hmo norE!
1500kW on 245kHz.
BROADCAST BANDS
Short Wave reports by the 15th of the month
to Derek Bell c/o Practical Wireless, Fleetway
House, Farringdon Street, London, EC4A 4AD.
Medium Wave Logs to Charles Molloy, 132 Segars
Lane, Southport, PR8 3JG.
AMATEUR BANDS
Logs covering any Amateur band/s in band/
alphabetical order by the 25th of the month to
Eric Dowdeswell G4AR, Silver Firs, Leatherhead
Road, Ashtead, Surrey, KT21 2TW.
AVAILABLE NOW!
REPRINT OF
PW's
TELE -TENNIS SERIES
TELE TENNIS SCORING UNIT
September :5
Some readers have queried the origin of
the timing signals used for this unit. The
signal Q3 originates at pin 13 of IC53, signal
SP2 at pin 3 of IC56 and signal SP6 at pin 8
of IC57. Note also that IC32 is shown as a
7410 which should read 7400, as in circuit
diagram.
78
duly- November 74
Send 75p 4- 10p (post & packing) to:Editor (PW Teie- Tennis),
Fleetway House, Farringdon Street,
London, EC4A 4AD
Practical Wireless, May 1976
Greenbank Electronics
Established 1970
DIGITAL CLOCK
P.C.B. MODULE KITS
(ex. VAT, p &p)
With 8mm digits
29.29
With
£1 2.53
16mm digits
Features:-
*
*
High quality tibreglass P.C.B. 112 x 89mm (both
types). a case is available as illustrated. or you can
make your own.
All components mount on one side of the board for
neatness and easy construction.
AY- 5 -1224A chip and L.E.D.s 'plug-in' for simple
* assembly and
*
*
servicing.
Uses L.E.D. display (believed to have the longest lifetime of all electronic display types known at present).
A single 12V, 500mA. 50 Hz supply is the only input
required (e.g. our 2 x 6V Min. Tr. @ £1.52 ex. VAT,
etc.).
*
*
The illustration shows the two P.C.B. module kits already assembled, one has 8mm high digits,
the other has 16mm high digits. Also shown is an example of a completed clock.
Free on request: Data on AY -5 -1224 and MK50253 clock chips, 4 and 6 digit alarm clock suggested
circuits, quartz crystal timebase, and L.E.D. displays, (If you can send an S.A.E., it makes things a
little easier for us).
*
Eight pages of 'step -by -step' instructions are prosuccess
vided, and back up assistance if you need
it-
guaranteed! Suitable for even the absolute beginner.
12 or 24hr display modes.
Easily converted to give additional 4 range 'stop-
watch' facility, for e.g. darkroom timer.
All parts available individually at no increase in
Price-buy only what you need.
CLOCK CHIPS
Modules can be supplied already assembled and
AY- 5 -1224A 4 digit basic clock L3.50 MK 50253 4/6 digit alarm /snooze £5.50
tested for an extra 75p (+ VAT etc.).
ECONOMY RED LED DISPLAYS ('Class II' quality, but guaranteed by us, fully returnable if
Module kits include: P.C.B., AY- 5 -1224A chip,
not satisfied).
4 L.E.D. digits, transistors, diodes, resistors,
DL-707E /DL-704E 8mm (0.3 ") 70p. DL- 727E/DL -728E 12mm (0.5 ") Double Digit L1.80. DL -747E/
capacitors, fuse and holder, pins.
DL-750E 16mm (0.6 ") E1-50.
CA 3130 COS/MOS Operational Amplifier 75p
CMOS WITH DISCOUNTS! (Any mix: disc. 10% 25 +, 25% 100 +)
*
*
*
4000/14000
4001/14001
4002/14002
4006/14006
4007/14007
4008/14008
4009!14009
4010/14010
4011/14011
4012/14012
4013/14013
4014/14014
4015/14015
4016/14016
4017/14017
4018/
4019/14519
4020/14020
4021/14021
4022/14022
-
0.15
O-15
0.15
0.95
0.15
0.75
N/S
N/S
0.15
0.13
0.45
0.80
0.80
0.45
0.80
0.80
0.43
0.90
0.80
0.75
4023/14023
4024/14024
4025/14025
4026/
4027/14027
4028/14028
4029/
4030/14507
4031/
4032/14032
4033/
4034/14034
4035/14035
4036/
4037/
4038/14038
4039/
4040/14040
4041/
4042/14042
--
0.15
0.60
0.15
I.40
0.45
0.70
0-90
0-45
1.80
0.85
1.10
1.55
0.95
1.80
0.75
0.85
2.85
0.85
0.65
0.65
4043/14043
4044/14044
4045/
4046/14046
4047/
4048/
4049/14049
4050/14050
4051/14051
4057/14052
4053/14053
4054/
4055/
4056/
4057/
4059/
4060/
4061/
4062/
4063/
-------
Terms: C.W.O. Add VAT to all prices at
94
8 %.
-
0.80
0-75
1.15
4066/14066
4067/
4068/14068
4069/14069
4070/14070
4071/14071
4072/14072
4073/14073
4075/14075
4076/14076
4077/14077
4078/14078
4081/14081
4082/14082
1.10
0.70
0.45
0.45
0-45
0.75
0.75
0.75
0.95
1.05
1.OS
4085/
10.35
4086/
4089/
4093/14093
10.60
0.90
16-40
N/S
4094/
4095/
0.90
Post etc.,
---
U.K.
10p
0.55
2.95
0.15
0.15
0.15
4096!
4097/
4099/
0.15
0.15
0.15
4700/
015
7083/
---
0-85
2-93
1.50
O-15
0.15
0.15
0.55
0-35
0.65
0-65
1.50
0.85
-
4501/
4502/4502
4505/
4506/
4508/4508
4510/4510
4511/4511
4512/
4514/4514
-
4517/
-
4518/4518
4520/4520
4521/
1.50
4-23
1.25
0.13
4515/4515
4516/4516
0.13
1.00
3.30
0-33
2.35
1.10
1.15
1.05
-
4522/
4524/
4526/
4527/4527
4528/4098
4529/
4530/
4531/
4532/4532
4534/
4536/
4537/
4539/
4541/
-
2-33
1.10
3-40
1.00
1.00
2-00
1.50
4543/
4549/
N/S
4557/
1.50
1.20
0-85
1.30
0.63
4558/
4559/
4560/
4561/
4562/
4566/
4572/
1.25
1.60
6.00
2.85
15.25
1.05
1.80
4552/
4553/
4554/
-
1-30
2-93
8-05
3'30
-
1.20
0-70
0-70
4555/4555
--
4556/4556
3-10
4580/40108
4581/40181
4582/40182
4583/
-
0.90
1-93
I55
0.45
5.23
I.20
0-33
6-00
3-05
1.IS
0.71
4585/ 1.43
235
per order, export 75p (no VAT). All orders processed on day of receipt
GREENBANK ELECTRONICS (Dept. W5P)
New Chester Road, New Ferry, Wirral, Merseyside, L62 SAG, England. Tel
3391
FREE SUPER SOLDER BOARD WITH EVERY DEC
PUSH COMPONENT -IN
BUILD CIRCUITS EASILY
NO SOLDERING
s
1
Nn
\tir`
44\
f oi
AO
100
O
(2§ZYk
P.B. Electronics (Scotland) Ltd.,
57 High Street, Saffron Walden, Essex.
Tel: Saffron Walden (0799) 22876.
Pruni(td fVire /ecs, :1,0 /976
Designing circuits is easy with DeCs, just plug in your components. Each
DeC breadboard is complete with step -by -step instructions. When circuit
is designed, take components out and use them again OR plug components
into SUPER SOLDER BOARDS for a perfect, finished P.C.B.
4)
i-
P. B. Electronics (Scotland) Ltd., 57 High Street, Saffron
Essex. Please find enclosed P.C. /Cheque value £
TO
Walden
+ Free Super Solder Board £1 .80
T -DeCs + Free Super Solder Board £3.87
U -DeCA + Free Super Solder Board £4.31
S -DeCs
FULL POSTAL ADDRESS
2az
79
RETURN OF POST MAIL -ORDER SERVICE
DISCO SPEAKERS
BAKER MA 1 OR 12" í1 50 BAKER
HIGH QUALITY- BRITISH MADE
JUST RELEASED
1
watt
R.C.S. 100
VALVE AMPLIFIER
Post 80p
30- 14,500 c /s, 12in. double
cone, woofer and tweeter cone
together with
a
BAKER
ceramic
magnet
assembly
having a Bus density 01
14,000 gauss and a total Bun
of 145,000 Maxwells. Bass
resonance 40 c/s rated 25
watts. NOTE: 3 or 8 or
15 ohms most be stated.
Four inputs. Four way mining, master volume, treble and
bass controls. Suits all speakers. This professional quality
amplifier chassis is suitable for all groups, disco. P.A., where
high quality power is required. 5 speaker outputs. A, C mains
operated. Slave output. Produced by demand for a quality
valve amplifier.
Suitable carrying cabinet £14.
Price L85 carr. 82 50
ANOTHER R.S.C. BARGAIN
!
ELAC 9 + Sin. HI -FI SPEAKER TYPE S9RM
This famous unit now available, 10 watts, 8 ohm.
Price
£3.45
Post 4op
8" or 10" x 6" ELAC
HI-FI SPEAKER
Dual cone plasticised toll surround. Large ceramic magnet.
50 16,000 cps. Baas resonance
55 cps. 8
ohm impedance.I
10 watts.
E4. 35
loin round [4.95.
and instructions.
"25"
GROUP
MODEL
For 13
B ".
16
Sin. or
81n, speaker
-
12in.
I2in
25
WATTS 852
L3.60
CHANNEL TRAN-
/5.20
/3.95
THE "INSTANT" BULK TAPE
ERASER & HEAD DEMAGNETISER.
Suitable for canettes, and all sizes of
tape reels. A.C. mains 200 240V.
Leaflet S.A.E.
/4.35
All purpose transistorised.
Ideal for Groups, Disco and P.A.
4 inputs speech and music. 2 -way
mixing. Output 8/15 ohm A.C. mains.
£49
£1 00
Latest 100 watt Model as illustrated
[68
Separate treble and bau controls.
Guaranteed. Details S.A.E.
.
80
is cut out for
85p. Rosewood Version £8 50.
Carr. 85p. Baffle could be cut for larger speaker.
Xó
P.W. SOUND TO LIGHT DISPLAY
(FOUR FOR
LIso)
Discounts for quantity.
post 30p.
FlusDensity
Useful response
8
16,500 gauze
20- 17,000cps
or 15 ohms models.
L17
80pt
Components Liait
full range reproducer for
high power, Electric Guitars,
public address, multi -speaker
6lln Woofer. 8750. Carr.
Complete kit of parts with R.C.S. printed circuit. Three
channels. 600 to 1,000 watt each. As featured in
December Practical Wireless.
Price
Cabinet extra £3.
£12.50
inch PHILIPS LOUDSPEAKER
8
4
ohm,
4
watt. ceramic magnet
E
I.95
MAINS TRANSFORMERS
8
VOLT
12 VOLT
18 VOLT
00 VOLT
1
I AMP. £1 .00
300 MA. £1.00
AMP. £1.00
AMP. 11.75 1 AMP.
E.M L TAPE
'.
3
AMP.
750 MA.
£1
.40
£I.30
AMP. £2.00
£2.00 3AMP. £220
2
MOTOR
21in.
pote, 240 v. Size 3;
1200 rpm. Spindle ,t in. diameter. 120v version 75p.
4
LI .85
£ 15.50 t
BO
AUDITORIUM
15in. 45 watts
A high wattage loudspeaker
of exceptional quality with a
level
response
to
above
8.000 cps. Ideal for Public
Address, Discotheques. Electronic instruments and the
home Hi -Fi.
Bus Resonance
3bcps
Flux Density
15.000 gauze
Useful response 20- 14.000cps
8 or 15 ohms models.
Post 45p
L19.50
120V or 240V a.c. 2.400 rpm
2 -pole. Size 2
2 ;in,
El .25
Hi -Fi Enclosure
Post 35p
10p.
systems.
electric
organs.
Ideal for HI -Fi and
Discotheques.
Bus Resonance
35cps
15,000 MSS
Flux Density
Useful response 25- 16,000cpe
8 or 15 ohms models.
Post
E.M.I. GRAM MOTOR
RADIO COMPONENT
Minievsu.
25cpe
Bass Resonance
A
-
bus compartment
OFFERING 1001 USES for every type of healing and
drying applications in the home, garage, greenhouse.
factory available in manufacturing quantities. Approx.
size l0;
8;
jin. Operating voltage 2001250V. a.c.
250 watts approx. Printed circuit element enclosed In
asbestos fitted with connecting wires. Completely flexible
providing sale Black beat. British -made for use in photocopiers and print drying equipment.
Ideal for home handymen and experimenters. Suitable
for Healing Pads, Food Warmers. Convector Heaters. etc.
Most be clamped between two sheets of metal or asbestos.
etc., to make efficient clothes dryers, towel rails ideal for
airing cupboards. Ideal for anti -frost device for the garage
preventing frozen radiators or acting as oil sump healer.
Use in greenhouse for seed raising and plant protection.
Invaluable aid for bird houses, incubators. etc.. etc. Can
be used in series for lower heat. Or in parallel for higher
heat applications.
EACH
A high quality loudspeaker.
its
remarkable
low
cone
clear
resonance
ensures
reproduction of the deepest
bass. Fitted with a special
copper drive and concentric
tweeter cone resulting in lull
with
range
reproduction
remarkable efficiency In the
upper register.
AUDITORIUM
I2in. 35 watts
Teak veneered fin thick wood cabinet.
Size 18 ;in
181ín
filin. Weight
2316. This cabinet features a wide
mesh Silver Grill covering
separate
compartment for mounting Tweeters
or Mid -Range Horn. The fully sealed
HEATING ELEMENTS
40p
Carr.
QUALITY LOUDSPEAKER
ENCLOSURE
3 WATT AMPLIFIER. 4 Transistor
Push -Pull Ready built with volume, treble and
bass controls. 18 volt battery operated. Mains Supply £3.45.
ALL POST PAID
SUPERB HI -FI
I2in 25 watts
or in cabinet £58.
BARGAIN
ONLY
1
100 WATT DISCO AMPLIFIER CHASSIS
4 speaker outputs. vol., treble, bus controls
L52
STEREO VERSION OF ABOVE £085.
THIN
quality.
£ 9.50
AMPLIFIER
SISTOR MONO MIXER. Add
musical highlights and sound
effects to recordings. Will mix
Microphone, records, tape and
tuner with separate controls into
single output. 8 volt
WAFER
Post 80p
MAJOR 50 WATT
ALL PURPOSE
TRANSISTOR
GOODMANS CONE TWEETER
battery operated.
"50/15"
1x 15 " --1x 12" I00 WATT CABINET
Size 36" x 24" x IS" E63.50.
Ideal for Disco or PA work. High
£ 14.50
post S0p
L21.50 Cala
4
R.M.S.
L55
75p
LOUDSPEAKER
CABINET
WADDING 18in. wide, 20p 11.
BARGAIN
"50/12"
Post
-
3;in. diem. 18,000 C.P.S.
100
WATT
Post Sop
Sin 75 watt
8 or 15 ohms.
MODEL "C ". 30
20
12m.
Radez cabinet will accept 1 -12in.
bass unit, 1 Sin. mid range. 1 3in.
tweeter. Teak finish.
Grooved
front
L46,
£ I O.50
40 watt
3, 8 or 15 ohms.
8
gin.
10
E6 95
R.M.S.
Post 50p
"35"
GROUP
GROUP
Post
859
70
WATT
£8.95
12ín 30 watt
3, 8 or 15 ohms.
Fluted Wood Fronts
13
Post 502
Bass resonance 55 cps.
12in 80 watt professional
model. 8 ohms or 15 ohms.
2 50
50
E 14
or 8 or 15 ohms.
3
Robustly constructed to stand up to
long periods of electronic power.
As used by leading groups.
Useful response 30- 13,000
cps.
GROUP
10in. speaker.
R.M.S.
L43
BAKER SPEAKERS
"BIG SOUND"
TEAK VENEER HI -FI SPEAKER CABINETS
MODEL "A ". 20
For 12 In. dia. or/
50
WATT
Module kit, 30- 17,000 cis
with tweeter. crossover, bate
Please stale
CABINETS
2 x 12"
for Disco or PA all fitted with carrying handle. and cornera.
Black finish.
Other cabinets in stock.
Cash price includes VAT
Manual
containing
crossover data and cubic tables, 68p
plans, designs.
CROYDON
S
WHITEHORSE (ROAD,ICRO
SPECIALISTSopen93769TEHORSE
Access & Barclay cards welcome.
Rail
Slhurst.
Tel. 01
-6114 1663
Practical Wireless, May 1976
BE
Dept
BAMBER ELECTRONICS
PIN, 5
STATION ROAD, LITTLEPORT, CAMBS., CB6 10E
Telephone: ELY (0353) 860185
1
SMALL MAINS SUPPRESSORS (small chokes.
ideal for radio. HI -FI inputs. etc.) approx. fin x
/fin, 3 for 50p.
PERSPEX TUNER PANELS (for FM Band 2
tuners) marked 88 -108 MHz and Channels 070,
clear numbers, rest blacked out, smart modern
appearance, size approx. Skin x 1í1n. 2 for 35p.
Multiturn Pots, 10 turn, fin spindle (ex- equip),
following velue. available, 2kohm, 5kohm,
400ko ,u. C1 each
Lead suppressors (IOkohm) for mobile plug
leads. 4 for Sop.
1mA Meters. 2 in square. plastic fronts (these
have a paper scale stuck over the 0.19mal marked
0-1mA which is easily peeled off and an internal
18K resistor which Is easily removed). í1.7S
each or 2 for t3.
AS Midget 3 pole 4 way, rotary switches.
40p each
SPECIAL OFFER
Miniature SOOhm Coax, high quality, PTFE
insulation and blue PTFE cover. solid silver
plated Inner, and silver plated brad, approx 3m.
overall diameter (ideal for unit wiring of RF
stages up to 23cm., etc.), 4 metres for Sep.
TRANSISTOR HEATSINKS, to take 2 x TO18
transistors. screw In clamps, block slze x f
fin, with holes for mounting, 3 for Sop.
HIGH QUALITY SPEAKERS, afin x 8ln elliptical,
only tin deep, inverse magnet, 4 ohms, rated up
to 10W, [1-SO cacher 2 for C2.7S (qty discount
available). + 2S% VAT.
TV
TV
TV
TV
PLUGS AND SOCKETS
Plug (metal typa). 5 for 500
Sockets (metal type). 4 for Sop.
Line Connectors (back -to -back sockets),
for Sop. Please add 2S% VAT.
2-6pF. 10mm circular ceramic trimmers (for
VHF.UHF work) 3 pin mounting. 5 for Sop.
TO3 translator insulator sets. 10 for Sop.
handles. mixed cola.
PC Board Withdrawal
for Sop.
Solder. 20 SWG. 60140 alloy. approx 8 yds for tip.
MINIATURE
fir hole, puns enclosed, with covers o9
chassis mounting. or van be used for in -line
connectors) Bargain pack of 3 plugs + 3 sockets
+ covers.
PROGRAMMERS (magnetic devices). Contain
9 mlcroswltches (suitable for meine operation)
with 3 rotating came, all Individually adjustable,
ideal for switching disco lights, displays. etc..
or Industrial machine programming' (Need
slow motion motor to drive cams. not supplied)
9 switch version LI -SO, or 15 switch version t2.
HEAVY DUTY HEATSINK BLOCKS, undrilled,
base area 2fin x tin, with 8 fins. total height
21in SOp each
5V RELAYS, Continental type. 2 pole change
over. 35p
RUBBER MAGNETS fin square. with mounting
hole, 20 for 30p.
SPERRY 7-SEGMENT P.O.D. DISPLAYS, digit
height 0.31n red, with decimal points, 150V to
200V (nominal 180V) operation. These are high volt Industrial type and therefore brighter than
normal displays. All brand new. AT THE
BARGAIN PRICE OF Sep PER DIGIT. TYPE 332
(two digits in one mount) [7 each, TYPE 333
(three digits on one mount) [1 -Se. (Sorry, no
single digit available.) Data Supplied.
8
BSX20 (VHF OsOMult). 3 for 50p.
BC108 (metal can), 4 for 50p.
PBC 108 (plastic BC108), S for Sop.
0C200 Transistors, 6 for Sop.
BFYS1 Transistors.
1
for sOp.
BCY72 Transistors, 4 for 50p.
PNP audio type TO5 Translators. 12 for 25p.
BF152 (UHF amp/mixer), 3 for SOp.
BAI51 Varice Diodes, 4 for Sep.
)fin polythene
Chacals mounting fuseholdere.
for 30p.
Mullard Tubular ceramic trimmers.
6 for Sop.
8
1
4
4
.' e.
mixed.
some coded.
20
for
14
DIL
type,
2Sp.
1
-180F.
untested.
PLUGS ANO SOCKETS
BNC Socket (Single-hole mounting type) Exequipment (special offer) 3 for 50p.
BNC Plugs (ex- equipment), 5 for [7.
N -Type Plugs 50 ohm, sop each, 3 for E1-50.
N -Type Sockets (4 -hole chassis mounting. 50
ohms (a small coax lead type). 50p each.
PL259 Plugs (PTFE). brand new, packed with
ducer..
or 5 for t3.
SO239 Sockets (PTFE), brand new (4 -hole fixing
tYpe). SOp each ors for [2P25.
25 -way ISEP Plugs and Sockets, by sal It plug
« lekt)
Plugs and sockets sold separately at 25p each
Bingen Round Free Skts. 3 pin, for mains input
on reel equipment, etc., 2Sp each.
Bulgin Fiel 2 -pin Flex Connectors non -reversible
/Op each.
PRACTICAL WIRELESS T.V. SOUND TUNER
IF Sub -Assembly (G8) £6.80. P & P 55p.
Mullard ELC1043 Varicap UHF Tuner £4.20. P & P 30p.
3 -way Station Control Unit £1 -20. P & P 25p.
6 -way Station Control Unit (Special Offer) £1 -00.
Resistors, Caps, Semiconds etc. £5.22. P á P 55p.
Printed Circuit Board £1 -00. P & P 25p.
24
VAT to price
of goods.
P
á
P all
items 65p.
Callers welcome at shop premises.
MANOR SUPPLIES
172
WEST END LANE, LONDON NW6
(Near W. Hampstead Tube Stn.) Tel.
01
-794 8751
PLEASE MENTION
Mobile Converters. 24V DC input 13.8V at
approx 3.4A DC output, fully stabilised. C3-55
each (Ideal for running 12V car radio from 24V
lorry battery).
Pkts. of 2BA Nuts (the sell -locking ones with
the nylon insert) 100 for Sop.
Spirslux Tools for the electronic
enthusiast. Screwdrivers, Nut Spanners, BA and
Metric Sizes, pop rivet guns. etc. S.A.E. for list
We now stock
Cans. fin square. suitable for rewind,
f
I F 3
WHEN REPLYING TO
ADVERTISEMENTS
6
V
Miniature earphones with min jack plug. 2for
SOp +25% VAT.
Dubllier Electrolytics, 50uF, 450V. 2 for Sop.
Dubiller Electrolytics, 100uF. 275V, 2 for 50p.
Plessey Electrolytics. 470uF, 53V, 3 for 50p.
TCC Electrolytlos. 1000uF, 30V, 3 for sip.
Plessey Electrolytics. 10000F. 100V, 40p each
(3 for El).
Dubiller Electrolytics, 5000uF, 35V, Sep each.
Dubiller Electrolytics. 5000uF, 50V. 55p each
Dubiller Electrolytics. 5000uF, 70V. OSp each.
ITT Electrolytics. 0800+F, 25V. high grade, screw
terminals, with mounting clips, SOp each.
Plessey Electrolytic,. 10.000uF at 83V. 75p each.
Plessey Cathodray Capacitor., 0-0 4uF at 12 5kV
DC. Screw terminals. t1-50 each
PLEASE ADD 2S% VAT TO ALL CAPACITORS
CAPACITORS AVAILABLE
AT BARGAIN PRICES, S.A.E. FOR LIST.
A LARGE RANGE OF
&
TYPE 14.4. 14V at 4A.
DIECAST BOXES (appro. size in inches)
4-3x2.3x1-2
4.8x2.3x1 5
4 8%3-8x1
iSp
7Sp
lip
4.8x38x3
8 8x48x4
[7.00
t1.45
[1.55
[2.25
10 B x 8
C2.25
4 8
81
3
x
4
x
8 x
8
2
2
83 x5 8x2
81.85
8 x 2
Please add 8% VAT
WELLER SOLDERING IRONS
EXPERT. Built- in- spotligh' Illuminates work
Pistol grip with fingertip trigger. High efficiency
copper soldering tip.
EXPERT SOLDER GUN. 15.50 o VAT (54p(
EXPERT SOLDER GUN KIT (spare bits case.
etc
t9.50 u VAT (7sp)
SPARE BITS, PAIR. 26p + VAT (2p)
)
MARKSMAN SOLDERING IRONS
SP15D 15W [2.52+ VAT (20p)
SP25D 25W C2.52 + VAT (20p)
SP2SDK 25W + bits, etc. kit 13.12 « VAT (2Sp)
B ENCH STAND with spring for Marksman Irons,
11.50 o VAT (lop)
SPARE BITS
MT8 for 15W, alp + VAT (3p).
MT4 for 25W. 35p + VAT 3p).
TCPI TEMPERATURE CONTROLLED IRON.
Temperature controlled iron 5 PSU. [18.43
+ VAT ([1 47).
SPARE TIPS
Type CC single flet, Type K double flat line tip.
90p each + VAT (Sp).
ALL SPARES AVAILABLE
MULTICORE SOLDER
Size 5 Savbit 18 s.w.g. in alloy dispenser. 32p
+ VAT (3p).
Size CISAVI6 Savbit 18s.w.g., Sip + VAT (ip).
Size 12 SAVBIT 18. w.g. on plastic reel t1'SO
VAT (lip)
MINIATURE PLIERS High quality 'Crescent'
mods in USA. 94.35 u VAT (35p).
SIDE CUTTERS. high quality -Crescents, made
in USA. £5.45 + VAT (44p).
PACKING (UK ONLY).
SAE with ALL ENQUIRIES Please.
J. BIRKETT
Radio Component Suppliers
25
The Strait, Lincoln, LN2 1JF
Telephone:
20767
TO .5 VOLT SILICON SOLAR CELLS (u) 35p each.
VOLT GREEN MAINS NEONS (áj 2Sp each.
SPECIAL OFFER 20 SILICON NPN PHOTO TRANSISTORS
-3
250
Untested
(al
LI.
50 TRANSISTOR ELECTROLYTIC CAPACITORS @ 57p.
25-- 25pí TUNING CAPACITORS with S.M. Drive (4. 38p.
500 -1- 500
VHF DUAL GATE MOS FET like 40673 (@i), 33p or 4 for L1 10.
LARGE PACKET OF 703, TIP SERIES MICA WASHERS @ Sop.
20 ITT BRANDED 250mW ZENERS Assorted (a) 75p.
20 STC SILICON 750mA DIODES Assorted PIV's @ Sop.
}
.
SUB- MINIATURE CERAMIC PLATE CAPACITORS Assorted
from 3-3 to Oluf at 57p.
VHF TUNING VARACTOR DIODES Untested 20 for 45p.
POSTAGE STAMP TRIMMERS IOpf, 30pf, 50pf, 150pf. 750pf, I000pf.
100
All at 6p each.
ASSORTED WIRE WOUND RESISTORS I to IO Watts @ S7p.
14 Strand 0048 PVC CABLE @ L3 per reel.
PLASTIC TRIACS 400 PIV 6 Amp @ 60p.
PLASTIC SCR'S 400 PIV 6 Amp @ 40p.
LARGE PACK OF POLYESTER CAPACITORS approx. 300 to 500
Pieces @ LI.
TAPE RECORDER DIGITAL MECHANICAL COUNTER @ 20p.
200 ASSORTED TUBULAR CERAMIC CAPACITORS @ S7p.
400 PIV 10 Amp STUD MOUNTING TRIACS @. 60p.
35 ASSORTED PRE-SETS and SLIDERS 1ái S7p.
STACKPOLE 5 Amp 240 Volt ROCKER SWITCHES @ 18p each, 4
for 60p.
TAG ENDED ELECTROLYTICS I000uf 64v.w., 2j" x 1")o@ 25p, 3300uí
60
500yd Reel of
II"
64v.w., size 24" x
PRACTICAL WIRELESS
SPECIAL OFFER,
MAINS TRANSFORMER.
OSp
Terms of Business: CASH WITH ORDER. MINIMUM ORDER f1. ALL PRICES INCLUDE POST
PLEASE ADD VAT AS SHOWN. ALL GOODS IN STOCK DESPATCHED BY RETURN.
Add
lines) Tuesday to Saturday
PLEASE ADD 8% VAT UNLESS OTHERWISE STATED
PLEASE ADD 8% VAT UNLESS OTHERWISE STATED
BARGAIN OFFER
MIXED COMPONENT PACKS. containing resietors, capacitors, switches, pots. etc. All n w
(random sample bag revealed approx. 700
Items). t2 per pack, while stocks last.
TUNED COILS, 2 section coils. around 1MHz.
with s black smart tuning knob. which moves
an internal core to very the Inductance, many
easily rewound. 3 for Sep.
TWIN I.F. CANS, approx. Lin x fin x 1in high,
around 3 S-5MHz. 2 separate transformers in
can. internally screened. 5 for 50p +25% VAT
(2
@ Sop,
@ 45p.
4700uf 40v,w., size 2.1" x
30 watt NPN @ 7.2p, PNP (a) 2Sp or
PLASTIC POWER TRANSISTORS
3Sp pair.
BYX 95 6250
PIV Amp SILICON DIODES @ 12 for LI .08.
TRANSISTOR RF CHOKES2-5MH (al I2p, IOMH Tapped @ 5 MH @ 1Sp.
BD 187 4 Amp NPN POWER TRANSISTORS 40p each or 4 for LI -35.
50 ASSORTED BRANDED TRANSISTORS NPN and PNP some with
1
house numbers and some data at 95p.
Volt NPN TRANSISTORS BF 177 120 MHz 600mW @ 6 for S7p.
ASSORTED SILVER MICA CAPACITORS 100 for S7p.
2.500 SOLID DIELECTRIC VARIABLE CAPACITORS @ 33p.
ITT PMT2R METALISED FILM CAPACITORS I -5uf 100v-w. @ 6
for 30p.
ISOuf IOv.w. REVERSIBLE ELECTROLYTIC CAPACITOR size ITSZ" x
@ 6 for 30p.
25 ASSORTED TRANSISTOR I.F. TRANSFORMERS @ Sip.
All items VAT PAID. Please add 20p post and packing for orders under L2.
100
"
Over L2 Free.
Practical Wireless, May 1976
81
ENGINEERS
SpNedlita rn!2
Capacitive discharge
electronic ignition
YOURSELF FOR A
BETTER JOB
WITH
Do you want promotion, a better
job, higher pay? "New opportunities" shows you how to get
them through a low-cost, Home
Study Course. There are no books
to buy and you can pay as you
learn.
=
1
THE KIT COMPRISES EVERYTHING NEEDED
Ready drilled pressed steel case coated in matt black epoxy resin, ready
drilled base and heat -sink; top quality 5 year guaranteed transformer
and components, cables, coil connectors, printed circuit board, nuts.
bolts, silicon grease, full instructions to make the kit negative or
positive earth, and 10 page installation instructions.
OPTIONAL EXTRAS
1
Electronic /conventional ignition switch.
Gives instant changeover from "Sparkrite" ignition to conventional
ignition for performance comparisons,-static timing etc., and will
also switch the ignition off completely as a security device, includes
switch connectors, mounting bracket and instructions. Cables excluded.
Also available RPM limiting control for dashboard mounting
(fitted in case on ready built unit).
For Crypton tuning and fitting service
-
1
Improve performance &economy NON
I
I
(laic* installation
no ovine mod'&st oll
required
Electronics Design Associates, Dept., PW/5
82 Bath Street, Walsall, WS1 313E. Phone: (0922) 33652
I
I
I
Name
Address
Mk. 2 DI
Mk.
2
4
V Aas.
Kit O E11.80
IZZ;zy
Ready Built Negative Earth O E14.97
Mk. 2 Raldy Built Positive Earth O E14.97
1
enclose cheque /PO's
forí
I
4.
11.11
E2.42
MI
CUT OUT THIS COUPON
Send SAE if brochure
only required.
MI =I
n
E
'i
Tick or state subject of interest.
Post to address below,
ELECTRICAL &
Radio, Servicing & Painting &
ELECTRONICS
Repairs
Decorating
Practical Radio &
Radio Amateur's
Electronics
Exam.
ò MECHANICAL
(with KIT)
A.M.S.E. (Meth.)
Electronic
AUTO & AERO
Engineering
General Mech.
Certificate
Motor Mechanics
Eng.
C.
&
G.
Motor
V.
Inst. Engineers &
General Elect. Ent
Mechanics
Technicians
Certificate
General Auto
Maintenance
C. & G. Elect.
Engineering
Engineering
Installations
A.M.I.M.I.
Welding
Elect. Install. &
Air Registration
Work
Board Certs.
C. & G. Elect.
M.A.A. /I.M.I. Dip. MANAGEMENT &
PRODUCTION
Technicians
Computer
Programming
CONSTRUCRADIO &
TIONAL
TELECOMInst. of Cost &
MUNICATIONS
Heating, Ventilating Managements
&
Air
Conditioning
Accts.
Colour TV
Servicing
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Draughtsmanship
D RAUGHTSC. & G. Telecoms.
& Design
MANSHIP &
Technician's Cert.
DESIGN
L.I.O.B.
C. & G. Radio,
General
Carpentry &
TV & Electronics
Draughtsmanship
Joinery
Mech. Cert.
A.M.I.E.D.
Plumbing
Radio & TV
Technology
Engineering
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Course
General Building
Draughtsmanship
,
'
1
1
I
G.C.E.
-58 '0'
-over
& 'A' Level Subjects
10,000 Group Passes!
1
i
Aldermaston College
Dept. TPW 17, Reading RG7 4PF.
also at our London Advisory Office, 4 Fore Street Avenue,
Moorgate, London EC2Y SET. Tel. 628 2721.
1
NAME (Block Capitals)
1
1
ADDRESS
Cheque No.
onition Changeover switches O E4.30
R.P.M. Limit systems in above units
82
1
PRICES INCLUDE VAT, POST AND PACKING.
OST "DAY!
ever did.
''
Sparkrite Mk. 2 is a high performance, high quality capacitive discharge,
electronic ignition system in kit form. Tried, tested,. proven, reliable
and complete. It can be assembled in two or three hours and fitted in
15/30 mins.
Because of the superb design of the Sparkrite circuit it completely
eliminates problems of the contact breaker. There is no misfire due to
contact breaker bounce which is eliminated electronically by a pulse
suppression circuit which prevents the unit firing if the points bounce
open at high R.P.M. Contact breaker burn is eliminated by reducing the
current to about /50th of the norm. It will perform equally well with
new, old, or even badly pitted points and is not dependent upon the
dwell time of the contact breakers for recharging the system. Sparkrite
incorporates a short circuit protected inverter which eliminates the
problems of SCR lock on and, therefore, eliminates the possibility of
blowing the transistors or the SCR. (Most capacitive discharge ignitions
are not completely foolproof in this respect). All kits fit vehicles with
coil /distributor ignition up to 8 cylinders.
'phone 10922133008.
This easy to follow GUIDE TO
SUCCESS should be read by every
ambitious engineer. Send for this
helpful 44-page free book NOW!
No obligation, nobody will call on
you. It could be the best thing you
CHOOSE A BRAND NEW FUTURE HERE
Smoother running
Instant all-weather starting
* Continual peak performance
* Longer coil /battery /plug life
Improved acceleration/top speeds
* Up to 20% better fuel consumption
*
*
CALLERS WELCOME.
MORE PAY!
Postcode
Other subjects of interest
Age
1
Accredited by C.A.C.C. Member of A.B. C.C.
HOME OF BRITISH INSTITUTE OF ENGINEERING TECHNOLOGY
Practical Wireless, May 1976
arcla
TECHNOLOGICAL
PRECISION PRODUCTS
ELECTRONICS
The NEWEST from
NOVUS-the 4525
I
,_,./---,
-/ 0
PROGRAMMABLE SCIENTIST
The NEW
100
Step Programmable Scientific Calculato
N
time and effort with complicated problems.
Saves
THIS IS TRULY AN
UNBEATABLE MACHINE!
-2
as
NOVOUS
4520. Exactly
£9,M
above but non -programmable
4515 MATHEMATICIAN
LL g
also the
.i5 V.A.T
+ 8%
Recommended
Prim
This
soft
is
£42.69
V.A.T.
ALGEBRAIC
CBM SR4148
12digit 2exp.
inc. ch.
£31.50
2exp.
616.69
ing.
NOVOUS
L18 25
NOVOUS 6020 8 -digit Financial
£1825
NOVOUS 6025 8 -digit Financial
100 step programmable
147.95
NOVOUS 6030 8 -digit statistical
L18.23
NOVOUS 6035 8 -digit statistical
100 step programmable
647.95
ADD 8% V.A.T. + 55p. p.&p.
Superb
CASIO fx -20
The
All the
-digit mantissa or 6digit mantissa and 210'9
digit exponents.
to 10-'9 Algebraic logic.
Bright Green display
Full floating point with
underflow. Overflow and
a
0.O
negative indicators. Sin,
Cos, Tan, Inverse Sin.
Inverse Co,, Inverse Tan.
ONLY
Log x and Inn ex, xt',
Reciprocal. Degree Radian conversion. Memory.
+ 8% VA.T. Exponent key.
£15.69
ALSO THE LARGER
Includes in addition
key, IT key.
x'
a
FUNCTIONS!
PULSTRONIC
The
with
NEW
iffirri
Hours
MrED
Secs
Self- .diusting
calendar
4
Auto-hold
fade -out
&
e®i
Date
EREI31 Date
Mins
+-
Moth
Day of week
A.M- Setting indicator
P.M. Setting indicator
the only watch we know that
gives the date and month in correct
order e.g. 29 02, 29th Feb. Single
button control, water /shock resistant anti magnet.c, silent. Accurate
to within a few seconds a year. Hrs,
Mins, Secs. Date + Mth, Day of week
(WE). Self-adjusting calendar. Auto
hold & fade -out. A-M. P.M. setting
indicator. In Satin finish stainless-steel
with polished bevelled edges. AND
matching bracelet. 10 FUNCTIONS. I Yr
Full Guarantee
I
This
is
li'
£37.40 plus £1.00 p.
Yx, Ex, in, log. 10x, Sin,
Tan, Cos. Inverse Sin,
Cos, Tan. D.M.S. key to
delete each
digit of
last entry. Key, key, Y'
key.Full memory.
I
&
p.
ORDER FORM
1
To: BARCLAY ELECTRONICS
1115,
11.
Dept CPW
FINCHLEY ROAD, TEMPLE FORTUNE, LONDON N.W.
All goods fully guaranteed. If not satisfied-money refunded if returned
undamaged within
1
p
£2690
IO
:
GREEN DISPLAY
8-digit and 2 exponents.
Single function colour coded
keyboard with
click- keys.Bright Green
display. CE key. C key,
7
days
PHONE CALLS AND PERSONAL CALLERS, WELCOME MON -THURS
BETWEEN 2 and 5 pm. SUNDAYS IO am - I pm. 01. 458 4755
Please send me
with /without optional mains adaptor.
total value
L
I
enclose chegaelmoney order
including 55p to cover packing.
NAME
Sign
key. Exponent
+8% V.A.T. change
10 -' °.
10p'
to
key.
Attractive soft Vynyl carrying case.
Maximum battery life 20 hrs.
MAINS ADAPTOR
Practical Wireless, May 1976
And N OW the watch
SR -50A
VATMAN SCIENTIFIC
by DECIMO
larger display,
10 -99.
+8% V.A.T.
£46.25 ÿA.T.
*£19.40 +V.A.T.
8%
AND THE de LUXE fix -IOI
with similar functions to fx -15 but
8- digits
+ 2
+8%
exponents. 109° *£24.03 V.A.T.
£13.50
ONLY
á
,ref
Both calculators complete with rechargeable batteries,
case
and
carry
adapter /charger,
Owners Manual.
fx -Is
ALL HAVE SEXAGECIMAL
DECIMAL CONVIERSION
OPTIONAL CASIO MAINS
ADAPTOR £2.95.
-
regression, mean, variance, standard
deviation, permutation, random number generator and 20 basic conversions
Three in(and their Inverses).
dependent user accessible memories,
Fixed or floating decimal option.
Reciprocal key.
to
E
TEXAS SR51 A
-
cos
aresin
plus many more are features of
this powerful scientific calculator.
Additional functions include linear
8
sin
C & CE key
arctan
reciarccos
natural log
to the x key
antilog 7r key memory + memory
memory exchange and memory cancel
PLUS
change notation
EE exponent
a degree radian
tan
10 digits + 2
exponents
Deg/
key S:itc
Key
'/x ReciV x Squaro Root Key
r/ Factorial Key
procal Key
arc
EE
inverse Trigonometric Key
Enter Exponent Key
+/- Change
CE Clear Entry Key
C
Sign Key
hyp Hyperbolic Function
Clear Key
Key
DIR Angle Change Key
log
inr Natural
Common Logarithm Key
ex e .:o the xth
Logarithm Key
yo y to the xth Power
Power Key
x V y The xth Root of y Key
Key
x:y Exchange Key
STO Store Key
RCL Recall Key
g Sum and
Store Key
+8% V.A.T.
11111,1.0-
-
function keys for
easy problem solv-
L13.50
6010 8 -digit conversion
oo
FUNCTIONS:
as
easily as
simple
arithmetic
probems. The SR -50
features an algebraic
keyboard with single
CMB 7919D 5 -digit + 2exp. or
8 -digit
612.50
REVERSE POLISH LOGIC
SINCLAIR SCIENTIFIC 5 -digit +
drop off
sir-iclair
procal key
ved
SINCLAIR OXFORD 3005 -digit +
2exp.
SR5OA
function
portable
slide rule calculator.
Complek scientific
calculations are sol-
CBM 1800D 87224
£2450
ROCKWELL 6IR 8 -digit conversion
£2195
including charger
ROCKWELL 63R 8 -digit + 2exp.
case you
SCIENTIFIC
Only }^ x 2" x H" yet has-8 digits or
5 + 2 exponent. Using the new chip, it
has full algebraic logic and many more
functions: Algebraic logic constant on
all four arithmetic functions
The SR -50 is the full
in ch.
£30 22
a
-
ÑW
ADVANCED CALCULATORS
SCIENTIFIC
VAT
p &p
the most unique clocklradio in the country today having
while the radio's onl
ONE OF THE MOST
xas
plus LI
button. (Automatic 80 minute 'sleep' button in
+ 8e/
SPECIAL OFFERS
V.A.T.
And the 4510 As the
Mathematician but non- LI3'49
programmable.
+ 8% V.A.T.
ALL WITH REVERSE POLISH LOGIC
Novnus Mains Ad'tr for the 4510 C2.90-
235.50
I} " high orange -glow digital readout which is completely
silent and non-pulsating. In a beautiful teak style cabinet with
up-to- dateVHF/MW radio. You can awake to soft music or alarm
and if you want up to 10 minutes more -just pres. the 'Drowse'
or the
8 -digit 100 Step programmable. 3
I evel
stack, recharger, case and
instruction manual E35 I0 + 8
C50
OUF PRICE
DECIMO DIGITAL
CLOCK /RADIO AS ON T.V.
8- digit
exponents
Common and natural logs and anti-log
Reciprocals
Yx
Sine, Cos, Tan. and their inverse
Xr
4 Roll stack
Register exchange
Sign change
IT
Degree radian conversion
Memory
Memlory + x2
Vynyl case
Rechargable (Recharger included in price)
(full instruction manual).
r
ADDRESS
rc'I
L3.
83
LIMITED OFFER
SPECIAL OFFER
1N4148
SWITCHING DIODES
BC107
For 30p 50 for £1.25
100 For £1.501000 for £10
10
-
BC108
100
-
BC109 9p each
for £7.50
POPULAR BRANDED TRANSISTORS
BC147
-
-
-
-
-
-discount.-
-
-
BF194
BF195
BC158
BC159
BC149
BC157
BC148
8p each. 100 for £6.50. Type numbers may be mixed for quantity
8
BF196
BF197
PIN DIL 741's NEW LOW PRICES
1
+25p10 +22p25 +20p100 +18p
Amp diodes IN4001 1N4002 IN4003 4p each 30 for £1
IN4004 IN4005 IN4006 6p each 30 for £1.50
ZENER DIODES BZY88 400 MW 3.3V to 33 VOLTS 7p each 100 for £6.00
MULLARD FERRITE CORES LA3 100 to 500 kHz 54p
LA5 30 to 100 kHz 81p, LA7 L 10kHz 81p
LA13 for W.W. OSCILLOSCOPE £1.50
AND CARBON FILM TYPES } WATT to 3 WATTS (25 DIFFERENT VALUES)
CARBON
RESISTORS
ASSORTED
300 for only £1.50
WIRE -ENDED GLASS NEONS 20 FOR £1
PLESSEY /T.C.C. CAPACITORS WIRE-ENDED 02/300V, 02/350V, .03/350V, 05/350V, 25/250V. 100 OF ANY VALUE
£2.00 OR 100 OF YOUR OWN CHOICE.
PLEASE NOTE THAT ALL PRICES INCLUDE POSTAGE AND V.A.T. AT 8 OR 25% AS APPROPRIATE
1
MAIL ORDER ONLY
XEROZA RADIO
1,
EAST STREET, BISHOPS TAWTON, BARNSTAPLE, DEVON
NEW CLOCK CHIPS
AND CLOCKS
INTRODUCING
THE
addition to National, Mostek and Caltex
clock chips, we are now selling a range of
General Instrument chips.
In
Newest, neatest
system ever
devised for storing small
parts and components:
resistors, capacitors, diodes, transistors,
etc. Rigid plastic units interlock together
in vertical and horizontal combinations.
Transparent plastic drawers have label slots.
ID and 2D have space dividers. Build up any
size cabinet for wall, bench or table top.
AS SUPPLIED TO POST OFFICE,
INDUSTRY & GOVERNMENT DEPTS.
SINGLE UNITS (1D) (Sins x 2 }ins x
2}ins). £240 DOZEN.
DOUBLE UNITS (20) (Sins x 4 }ins x
2 }ins).
L4.20 DOZEN.
TREBLE (3D) L420 for 8.
DOUBLE TREBLE 2 drawers, in one
outer case (6D2), L5-90 for 8.
EXTRA LARGE SIZE (6D1) ES 40 for 8.
PLUS QUANTITY DISCOUNTS!
Orders over L20, less 5 %.
Orders over L60, less 71 %.
PACKING /POSTAGE /CARRIAGE: Add 75p
to all orders under L10. Orders L10and over,
please add 10% carriage.
QUOTATIONS FOR LARGER QUANTITIES
Please add 8% V.A.T. to total remittance
FLAIRLINE SUPPLIES
124
84
(Dept PW5)
Cricklewood Broadway, London NW2
Tel. 01-450 4844
AY -5 -1202. 12 or 24 hour. 50 or 60 Hz.
Interfaces directly with Futaba SLTOI L4.76
1202. ON/OFF
AY -5 -1230. Similar to
programmable alarm. In 7 segment mode
can drive 5LT01, or BCD to drive logic or
LS 25
TV display chips.
MISTRAL CLOCK KIT
Uses AY -5- 1202 4 Futaba 5LT01. Complete
kit including
case.
L1158
CHEVIOT ALARM CLOCK
24 hour 4 digit alarm clock, 0-5in. green
display, tilt to snooze. Finished clock
01.85
not kit.
5LT01. Green Phosphor Diode.
Futaba 5LT01 display has 4 digits with
AM /PM. Seconds indication on colon.
LS80
Requires multiplexed input.
SLT02. Similar to 5LT01. Requires non£580
multiplexed input, e.g. MM5316.
5LT03. 5 digit multiplexed for use as
05.80
counter or DVM module.
-
rr o
TERMS: CWO, Access, Barclaycard (simply
quote your number and sign). Credit
facilities to Accredited account holders.
VAT: All prices
Hemel Hempstead, exclude VAT (8 %)
Herts HP3 9QRA P /P: I5p
68
Ebberns Road,
TEL: 0442 62757
MINISONIC
2
Electronic Music Synthesiser
As Demonstrated "live" at the Audio Fair 1975
Based on the original P.E. Minisonic, the Mk. 21s
a
three octave keyboard Instrument which sets
new standards of performance and flexibility. Designed for construction by the amateur electronics
enthusiast or do -it-yourself musician, the Mini sonic 2 has a truly "professional" sound which
has to be heard to be believed.
case plus
* Finished
panels
* Two(3Hz-VCOs
50kHz)
* VCOmodulation
cross
* Variable Portamento
* VCO sync. facility
* Fixed Variable Span
* Envelope
indicators
* Pan pots at output
Button
* Push
Patching
* Headphone
amplifiers
* Low Current drain
* Maine
/Batt.
Operation
A complete kit of parts is available to byild this
fabulous Instrument or to convert your Mk. 1
Minisonic.
Ready made instruments are also available, com-
plete with guarantee plus instruction booklet.
Want to know more? For full details send
9 x 4in S.A.E.
EßSOfl
a
3.
PEI9
318
Practical Wireless, May 1976
Thiele dram timing device, the dram being
calibrated to equal divisions for switch'
setting purposes with tripe which are
infinitely adjustable for position. They
are also arranged to allow 2 operations
per switch per rotation. There are 15
changeover micro switches each of
10 amp type operated by the trips,
thus 16 circuits may be changed per
revolution. Drive motor is mains
operated 6 revs per min. Some of the many uses of this timer are Machinery
control. Boller firing. Dispensing and Vending machines. Display lighting
animated and signs. Signalling, etc. Price from maker, probably over 120 each.
Special snip price 11996. 5100 Poet and VAT. Don't miss this terrific bargain.
CONTROLLER
Electronically change.
speed
approxl
from
mately 10 rev.. to
SPEEDS maximum. Full power at
All speed. by fingertip control.
Kit includes all parta, case,
everything and full Instructions.
12.60 plus 45p post and VAT
Made up model also available.
PERMEABILITY TUNERS
M.W. two otage ideal for
use with ZN414 or similar
circuit. Prie 16p each +
Post and VAT 15p.
BREAK -DOWN
Designed to operate translator seta and amplifiers.
Adtastable output 8v., 9v., 12 volta for up to
500mA (class B working). Takes the place of any
of the following batteries: PP1, PP3, PP4, PPG,
PP7, PP9 and others. Kit comprises: main
transformer rectifier, smoothing and load resistor.
condensers and Instructions. Real snip at only
1150. VAT 4: postage 80p.
HORSTMANN
NUMICATOR TUBES
digital
instrumente,
Twice Daily
All Day
Twice Daily
2
3
4
31^ wound wide angle 240 move-
All Day
Off
Off
on
Twice Daily
All Day
Continuously
5
Continuously
Suitable, of course, to programme other than central heating and hot water, for
instance, programme upstairs and downstairs electric heating or heating and
cooling or taped music and radio. In fact. there is no limit to the versatility of
this Programmer. Maine operated. Sin lin x lin x 21n deep. Price 64'25. 80p
Post and VAT. as Illustrated but la. case.
ment meters, lab mounting
fitted with external shunts, made
by Crompton Parkinson, brand
new, still in maker's cartons.
These are a real bargain at 660
each. Reasonable quantities
available in the following ranges 0 -11 amps,
0.20 amps, 0 -30 amps, 0 -40 amps, Poet and
MULLARD UNILEX
mains operated 4 + 4 stereo
system. Rated one of the finest performers in the stereo field this would
make a wonderful gift for almost
anyone In easy -to-assemble modular form and complete with a pair of
Goodmans speakers this should sell at
about 130 -but due to a special bulk
buy and ea an incentive for you to
buy this month we offer the system
complete at only 916.60 Including
VAT and postage.
A
VAT POp each.
TAPE DECK
In metal case with carrying
handle, heavy flywheel and
capstan drive. Tape erased
31. Mains operated on
metal platform with tape
head and guide. Not new
'
THIS MONTH'S SNIP
VAT and Postage 51.60.
HIGH POWERED TRANSFORMER
SOUND TO LIGHT UNIT
r
-
TIME SWITCH
Off
0
1
DC HIGH CURRENT PANEL
METERS
Add colour or white light to
your amplifier. Will operate
1, 2 or 3 lampa (maximum
450w). Unit in box all ready
to work. 17.95 plus 96 VAT
24 -HOUR
With 6 position programmer. When fitted to hot water
systems this could programme as follows:
Hot Water
Central Heating
Programme
counters,
timen, clocks, etc. Ill-vac XNII
Price 1116 each, 20p Post and VAT.
but guaranteed good workMg order. Price 6160 plus
UNIT
Contains hundreds of useful parts some of
which are as follows --88 silicon diodes equivalent OA91, 68 resistors, mostly 1 watt 5 %
covering k wide range of values 4 x 1 mfd
400v mfd condensers, 15 x 01 mfd 100v condement, 2 BF chokes 8 x B9 valve holders, 1
x 4H choke, 1 x 115v transformer, 1 boxed unit
containing 4 delay lines also tag panels, trimmer condensers, suppressors, etc., on a useful
chassis eised approx 9^ x 6^ x 7^. Only 76p
the 66 diodes would cost at least 10 times this
amount). This is a snip not to he missed. Pont
and VAT 76p.
MAINS TRANSISTOR PACK
For
0.0).70 photo transistor
HONEYWELL PROGRAMMER
DRILL
CONTROL
DRILL
Rated at 260 Watt., upright mounting varnish Impregnated. Its primary
is for 230/240 volts 50 cycles, it has four secondaries each 10v very high
current windings. Just a few of the circuits it can power are: 10.0-10v at
up toll amps; 20.0 -20v at up to 6 amps; single 10v at 26 amps; single 20v at
121 amps; single 30v at 9 amp.; single 40v at 45 amps. This can be used
for charging or for amplifiers, etc., there being an earth screen between
primary and secondaries. A transformer like this to -day would cost at
least E10 from the maker; however, we are making a epeeist offer at
1350 + 89p, post El + 8p each. Grab some while you can, our stock may
not last long.
t
and postage.
SPIT MOTOR
200 -200V Induction
motor,
driving a Carter gearbox with
a 11 output drive shaft
running at 6 revs p.m. for
roasting chickens, also for
driving
models -windmills,
coloured disc lighting effects,
etc. 1260 plus 60p post and
TWIN OUTPUT POWER PACKS
These have two separately H.C. smoothed outputs
so can operate two battery radios on a stereo amp
without cross modulation (they will of course
operate one radio- tape -corvette- calculator in fact any
battery appliance and will save their coat in a few
months). Specs: Full wave rectification, double
insulated mains transformer -total enclosed In a
bard P.V.C. ease -thee core maim lead-terminal
output -when ordering please state output voltage
45v, 0v, 75v, 9v, 12v or 24v.
Price 1S95. Post and VAT Included.
VAT.
OVEN THERMOSTAT
Made by the famous Diamond H
Company, this has (tensor Joined
by a capillary to a variable control
and when fitted with a knob is Ideal
for many ovens or processes, 50p
each + post and VAT 15p
ONLY LI
E
MAINS TRANSFORMERS
All standard 230-250 volt primaries
lv
6ßv
2.4v
6.3v
9v
9v
12v
12v
8.6v- 0.8.6v
16v
24v
24v
12.O.12v
66.6v
86-8v
25.0.26v
26v
2 amp A 6.3v
6 amp d 5v
27v
30v
80v tapped 76v a: 70v
230v-60mA & 6Sv
275- 0.270v at 90mA A 804v
EHT Transformer 5000v
23mA
50v
60v
1
p
amp (special) 1.78
amp
-86
2 amp
1.86
3 amp
1-75
1 amp
95
8.6 amp
9.60
11 amp
1.60
1 amp
1.00
1 amp
1.50
1 amp
1.50
2 amp
2.25
3 amp
3.80
1
6
SOmA
50mA
5
amp
1'20
1.20
1
50
2 amp
15 amp
3.50
1.95
8 amp
37 amp
4 amp
2200
1 amp
1 amp
460
7.60
4.50
16 amp
6.50
1.76
3
2-26
amp
(Intermittent)
Charger Transformers
8v and 12v
2 amp
6v and 12v
3 amp
ev and 12v
5 amp
Add 30p per Al to cover postage and VAT
Practica! Wireless, May 1976
-50 FOR SEVEN
LECTRIC MOTORS
powerful batt. motors as used in racing cars and
power models. Output and types vary for use in
hundreds of projects-Tools, toys, models, etc. All
brand new reversible and for 15.12v batta. Wiring
diag. Inc. VAT P Poet 40p. FREE plan for min. power
7
660
150
2.25
3.60
station.
B LACK
LIGHT
appear,
until the rays impinge on luminous paint or white shirts, etc. We offer 9^ 8w
tubes complete with starter, choke, lamp holder and starter -holder. Price 12.76
Poet
A
VAT
60p.
post.
only
Tubes
1$.
+ 30p
175 Watt model 16.50 + 92p Post and VAT.
As used In discotheques and for stage effects etc. Virtually no white light
MULTIPLE CONTACT PANEL
Size approx. 41 x 21^ have 200 contacta each across referenced for easy identification. Contact. are spring loaded and gold "pip ". Ideal for the circuit breadhoarding (resistors, etc., plag straight In) or for working out printed circuits, for
electrode novelties, pussies, combination locks, etc., ex -mused computer
panels, price only 12 + 16p. IE. only 1p per contact, probably less than the
value of the gold pip. Poet + lip.
Monthly list available free; send long stamped envelope.
TERMS: Where order is under 15 please add 30p surcharge to offset packing
expenses.
J. BULL (ELECTRICAL) LTD
(Dept. P.W.), 103 TAMWORTH ROAD,
CROYDON CRO IXX.
by Mulard, very popular
for circuite such as Infra -red burglar alarms, smoke
detectors, etc. A big buy enables us to offer at the
very favourable price of 26p each + 2p, or 6 for 61
+
8p.
Mlotcaw ich bargain, made by Pye, Honey-well,
Burgess and similar first class makers originally
for the Poet Office, in fact they have been fitted
to Poet Office Equipment which was never put
into use. They are a changeover microewitch with
10 amp contacts offered at the very low price of
20 for LI + 8p. Poet 40p + 3p.
Junction bolas tree. We are coming to the time
of the year when additional wiring and home
alterations are usually carried out and ae a
special offer to all buying our cable to install
immersion heaters, ring mains, etc., we are giving
free this month six Junction boxes with every
100 yard coil of 7/029 (4mm twin and earth
cable). Our price for this cable, which is only
approximately one half of the regular price
anyway, is 66 + 64p. Carriage 1260 + 20pdon't miss this bargain.
Super stick microphone. Japanese made, extremely
good quality and performance. Impedance
50 Kohn.. The microphone is intended for hand
bolding but stands ae available if required.
Price 1460 + E112p. Poet 40p + 10p.
Tuner Cassette as described in March "Practical
Wireless". Please note we can supply the ferrite
Blab and the Z.N. 414 1C. Price for these two
items 6925 Including post and VAT. Copy of
the circuit supplied on request.
Burglar Alarms. More and more burglars seem to
be thriving on the properties of people who cannot
be bothered to Install burglar alarms. We can
offer the intruder alarm as described in "Everyday
Electronics" September issue. This is a good
circuit and not too expensive. Price le 63.83
+ 81p. Post 40p + 10p.
Thermally protected motor. American made I"
stack. This revs. at 2400 RPM, suitable for fan
or similar application. Special feature Is the trip
which cute off the mains should the motor overheat. Price 11.110 + 13p. Post 25p + 2p.
Amplifier In ease with speaker, marketed by
British Relay. This is In good quality cabinet
with back and elliptical speaker. The amplifier
le the Newmarket PC 4 module, together with
volume control, else 91^ x 8" x 35 deep, the
amplifier can be powered by an Internal 9v
battery or from external mains source. Very
useful amplifier for around the home or in the
workshop for troubleshooting, or for testing out
a quick lash up. Limited quantity of these,
offered at bargain prices of 14 + Al. Peat 40p+ 10p.
Teak veneered doable cabinet. We believe that
this was made from one of the Leak systems.
deep made of thick
It is 26^ x 41" high x
board with sound /vent holes and should be ideal
to house amplifier and tuner. or amplifier and one
speaker. Very high quality cabinet which would
cost IA or E5 to make today. Price 12 + 50p +
80p + 20p.
Thaw Dimmers made by Ultra Electronics, this
is a variable controller which can be fitted behind
a panel or into a standard switch box and it will
control by 1260 watts along your similar noninductive load. Very special price only 68 +
24p + 30p + 3p.
Disco Black Light Lamp 176 watta- 210/240v
pear -shaped back outer glass which obscures all
visible radiation but emite long wave ultra violet
(black light). This lamp provides a convenient
way of fluorescing a discotheque, club, dance ball,
party b an d bring ,direct plug In replacement of
tungsten lamp it le very convenient for temporary
usage anywhere. Price 68.50 +50p. Poet 50p +4P.
lame more Relay bargains. Miniature plug-in
type with perspex dust cover 700 shin 12v DC
working. 4 sets of gold- plated changeover contact.
1/2 ampe. Normally an expensive relay. Our
price 61 + 8p .
Mains Relays 230/240v. AC operated with 10 amp
changeover contact., open type, one screw
fixing 3 sets changeover contacts A + Bp each.
Three Changeover perms covered plug-in types
6126 + 10p each, bases for same 30p + 2p each.
Available with following coil voltages 12v AC.
50v AC 230/240 AC. Also still available the most
versatile type 600 relay which, having a double
wound coil, is suitable for working off 8, 12 or
14v. DC or mains through aeries resistor. This has
multiple contacts and the price is 40p + 31, each.
Sound Transducer balanced armature type,
COO ohm Imp. In capsule, else diameter 11" by }^
thick. Useful in digital equipment or fo audio
monitoring, or as a microphone or speaker, good
quantities available. Basic price 60p + 4p lees
our usual quality discounts.
Verner Cook Replacements. 24 hour clock motor
8
with threaded driving shaft. Standard replacements in many Verner time switches. Price
6150 + 12p. Poet 30p + 8p.
Stereo Pre amplifier, Mallard reference LP1182/2.
This is a dual input hi-fi module, has a frequency
response of 20 HZ to 50 KHZ. Its sensitivity
160mV at input 1 or 329mV at input 2. The bass
and treble control ranges are plus or minus 14dB,
distortion better than .2%. All components are
mounted on printed circuit wiring board, overall
she of which is approx. 8" square. Connections
are brought out to 22 tags which provide for
high and low impedance inputs, stereo outputs,
been and treble lift., volume and balance controls.
We will supply complete with diagram of connections, price 6160 + 37p. Poet 80p + 7p.
Special Instrument offer is a Raglan made Salvo,
very sensitive precision instrument, full scale
deflection 7.0.7µA. This is a bench mounting
lustrament of extremely high sensitivity (SpA
per division) rise app ox. e1^ x 25" x 2".
Price 1960 each + 78p. Post 50p + 4p.
Photo Multiplies Tubes. U.S. made, R.C.A. type
No. 4556. These tubes have a gala of a million or
more -regular price around 180 each, our price
!S
54p each. Brand new In original maker's
85
.
`VAT INCLUSIVE
P -No
Add 20p P 6
TTLs by TEXAS
13p
20p
7400
74H00
1Sp
1Sp
7401
7402
7403
7464
74H04
7405
7406
7407
7408
7409
7410
17p
17p
17p
41p
39p
17p
22p
15p
20p
24p
74H10
7411
7453
7454
7460
7470
17p
18p
16p
29p
27p
74181
74181
7472
32p
7474
7474
7475
7176
7480
32p
Up
107p
107p
107p
107p
130p
138p
131p
31p
108p
1089
322P
lip
9p
9p
10p
lip
lap
13p
15p
12p
11p
13p
20p
17p
20p
12p
12p
OP. AMPS
301A
5367
709
741
717
748
776
1458
,'",;,.,°'
130
BD132
BD135
Up
80136
55p
79p
alp
24p
25p
25p
27p
28p
BD139
813140
BF115
BF167
BF170
BF173
BF177
BF178
BF179
BF180
BF181
85X19
lip
190
S5p
Sop
123p
2479
270p
S9p
Oip
210p
210p
145p
2500
/Op
299
29p
199
29p
1429
2009
1089
130p
1089
4071
1110p
lip
4072
4081
125p
199
200p
4082
4510
alp
4511
152p
169p
4518
4528
,
810p
14
24
FIXED -Plastic
Terminals
Positive
Amp
5V
12V
15V
18V
24V
3
7805
7812
1509
7815
150p
1509
1509
18Op
7818
7824
Amp
Negative
5V
12V
15V
18V
24V
7905
7012
7015
7918
7924
LM309K (T03) 5V
1
amp 1509
DUAL VOLTAGE
REGULATOR
± 15V 100 mA
pin DIL
Adjustable
by
324p
resistors
from ± 8V min to ± 20V max
VARIABLE VOLTAGE
REGULATOR
2V to 37V 150 mA
14
Pin DIL
MAIL ORDER
ONLY - PROMPT
DESPATCH
TIP34C
2N1131
13p
0C41
17p
19p
40p
34p
0C42
0C45
0071
TIP29A
TIP29C
TIP30A
70p
70p
19p
10p
19p
2N1132
2N1304
2N1305
2N1308
2N1307
2N1613
2Sp
50p
62p
611p
40p
300p
30p
25p
78p
40p
pin DIL
pin OIL
1S3p
Pro9. Op. Amp TO 99
7Sp
Dual Op. Amp. 8 pin DIL
CMOS /Bipolar Mosfet B pin DIL
741 14
Ext. Comp. 8
108p
Quad. Op. Amp.
14
pin DIL
609
1129
S5P
Quad. Low Noise Amp.
16 pin OIL
250p
Diff. Cascade Amp. TO5 /DIL 45p
CA 3053
250p
CA 3089E FM IF System 16 pin DIL
SOOp
CA 3090A0 FM Stereo Decoder OIL
ICL8038BC VCO Function Generator
000P
16 pin DIL
ICL8038CC VCO Function Generator
30p
18 pin DIL
LM 380N
2W Audio Amplifier
115p
14 pin OIL
Amp
14
pin
DIL
200p
LM 381N
Pre
Stereo
FM Stereo Decoder 14 pin OIL 220p
MC1310
13759
MC1312/3/5 SO Quad Decoder
MFC40008 IW Audio Amplifier PCB
UP
130p
MFC6040
Electronic Attenuator PCB
40p
NE555V
Timer 8 pin DIL
1089
NE558
Dual 555 14 pin DIL
PLL with AM Demod
NE56113
350p
16 pin DIL
3500
NE562B
PLL with VCO 16 pin DIL
200P
PLL 14 pin DIL
NE565
PLL Function Gen 8 pin DIL 16Sp
NE566V
PLL Tone Decoder 8 pin DIL 200p
NE567V
400p
Dual 587 18 pin DIL
2567
Diff. comparator 14 pin DIL 549
SN72710
Video Amplifier 14 pin DIL 1509
SN72733
SN76013N Audio Pwr Amp with let HS 1759
SN76023N Audio Pwr Amp with int HS 1750
TAA661B FM IF Amp Llm /Detector OIL 150P
3009
TBA641B Audio Amp 14 pin DIL
112p
TBA800
5W Audio Amp QIL
125P
TBA810
7W Audio Amp QIL
100p
TBA820
2W Audio Amp OIL
405p
TDA2020 20W Audio Amp OIL
XR2240
Prog Timer/Counterl6 pin DIL 400p
140p
ZN414
TRF Radio Receiver 7018
Basic data sheet on above ICs at Op each+
CA 3048
S.A.E.
OPTO- ELECTRONICS
PHOTOLEDs
TIL209
TRANSISTORS
ORP80
ORP81
33p
Red
TIL211 Green
TIL32 Infrared
02"
lip
Red
Green
7Sp
7Sp
Yellow
SEVEN SEGMENT DISPLAYS
Minifron 0.3"
3015F
DL704 Com. Cathode 0.3"
DL747 Com. Anode 0.6"
O
Com. Anode 0 6"
OPT O- ISOLATORS
Phototransistor TIL112 (IL 12) 6 Pin OIL
Photodarlington ILCA55
DRIVERS
6
Pin DIL
Quad Segment Driver 14 Pin Dd
75402 Hex Digit Driver 14 Pin DIL
Govt., Colleges,
etc. orders
accepted '
TIP2955
ZTX108
ZTX300
98p
Up
120p
43p
TIP38A
TIP36C
TIP41A
TIP42A
0C28
lip
159
329
alp
lip
299
32p
130p
160p
0p
25
151p
270p
75p
97p
120p
124p
160p
243p
290p
297p
360p
70p
78p
76p
TIP35C
lip
16p
lip
ZTX500
ZTX504
14p
32p
13p
19p
43p
19p
19p
19p
23p
23p
2N1711
2N4348
2N4401
2N4403
2N5089
2N5401
40360
349
32p
32p
Up
3N141
40603
40673
81p
92p
81p
63p
54p
TIS43
34p
38p
37p
2N6027
60p
0A81
10p
11p
0A85
01- 204 -4333
ENGINEER
7p
9p
OA90
0A91
0A05
0A200
Op
SP
0A202
Up
lop
1N916
1N4148
15p
32p
22p
22p
22p
BY100
0Y126
BY127
ip
1N4002
IN4004
1N4005
1N4007
SIp
lip
lip
14p
24Op
90p
22p
ZENER
2 7 to 1]V
I
400mW
W
119
AEY11
75p
Up
TUNNEL
VARICAP
33p
138105
NOISE
25J
l40p
BRIDGE
RECTIFIERS
to
50V
100V
2Sp
1A 400V
1A 600V
31p
37p
40p
48p
56p
7Sp
65p
70p
Up IA
220
19p
19p
22p
31p
15p
15p
6p
6p
7p
7p
Sp
1N4001
19p
43p
72p
1519
14P
14p
14p
14p
12p
11p
4p
RECTIFIER
27p
2A 50V
2A 100V
2A 400V
Up
Up IA 100V
Up 6A 50V
24p SA 100V
142p TRIALS
173p Amp Volts
34p
34p
34p
62p
43p
40361
Olp
40382
40410
40409
41p
40411
243p
59p
S9p
3 400
6 400
6 500
10 400
10 500
40430
40486
40660
DIAC
130p
162p
194p
200p
270p
108p
1089
105p
BR100
Mk II Drill
only
Stand
£8.00 p.p. 35p
£3.76 p.p. 35p
27p
SCR THYRISTORS
1A 50V TO5
43p
IA
4Sp
50p
53p
100V
T05
1A 400V TO5
3A 100V STUD
3A 400V STUD
7A 400V TO5 + HS
7A 400V TO5 + HS
8A 50V Plastic
12A 400V Plastic
16A 100V Plastic
16A 400V Plastic
16A 600V Plastic
07106
1509 2N3525
59p 2N4444
C10613
MCR101 27p 2N5064
Sip
87p
97p
1129
173 p
173p
1959
238p
879
2009
43p
RHYTHM GENERATOR
Semiconductor Kit for current
PW"
Project.
Includes
all
I.Cs., Trs., Diodes and OIL
sockets £14.00 inc. VAT and
97p P 6 P.
SANDHURST ROAD, LONDON, NW9
Tel.
INTRODUCING A
MINIATURE
PRECISION 12v. D.C.
DRILL DESIGNED FOR
THE ELECTRONIC
Sip
2N4871
TECHNOMATIC LTD.
54
Tel. 01- 977 -0878
DIODES
SIGNAL
0A47
9p
10p
0A70
2N29260G11p
2N4371
119A HIGH STREET,
TEDDINGTON TW11 8HG
lOp
2N2222
2N2369
2N2484
2N2904
2N2905
2N2906
2N2926RB
2N3904
2N3905
2N3006
2N4058
2N4060
2N4123
2N4124
2N4125
2N4126
2N4289
PRECISION PETITE
LTD. (Dept. P.W.)
SOP
PUJT
32p
22p
20
2142221
2N3053
2N3054
2N3055
2N3439
2N3442
2N3702
2N3703
2N3704
2N3705
2N3706
2N3708
2N3709
2N3707
2N3773
45p
37p
37p
37p
37p
27p
2N2160
2N2648
Up
Up
22p
Up
2N1893
2N2219
92p
UJTS
60p
2N897
2N698
2N706
2N708
2N918
2N930
81p
BF244
MPF102
MPF103
MPF104
MPF105
2N3819
2N3820
2N3823
2N5457
2N5458
2N5459
3N128
3N140
OSp
TIP35A
MPSU56
FET Op. Amp TO 0
Ext. Comp. 8/14 pin DIL
Int. Comp. 8/14 pin DIL
Dual
TIP32A
TIP32C
TIP33A
TIP33C
TIP34A
35p
24p
Up 0C35
Up
TIP31A
Up
35p
35p
75491
45p
211p
lap
Ext. Comp. 8 pin D L
OCP70
215p OCP71
2N5777
2159 LDRs
2159 ORP72
1
.,".4".."
FETs
BSX20
129
SIP
103p
75p
150p
2189
150p
166p
bap
alp
Sip
LINEAR I.Cs.
CA 3028A Diff. Cascade Amp. To 99
5 Transistor Array 14 pin DIL
CA 3046
4030
4042
4043
4046
4047
4040
4054
4055
4056
4060
TIP31C
17p
3900
lip
40594
40595
16p
1169
13p
999
1069
214p
187p
ICs
72p
19p
175p
BU105
312p
BU108
459
MJE340
819
MJ2955
MJE2955 107p
MJE3055 70p
MPSA06 17p
MPSA12 62p
MPSI:'06 lap
np
8F182
BF184
8F185
SF194
BF195
8F196
BF197
BF200
6F257
BF258
TIP30C
lip
í10p
VOLTAGE
REGULATORS
86
18p
35p
43p
10p
10p
130124
BD131
etc.
37p
37p
37p
37p
37p
32p
28p
27p
22p
20p
74194
74185
74198
74197
74198
74199
pin ,13p,
pin 15p,
723
lip
lip
80123
74194
67p
16
BCY71
BFR39
BFR40
BFR79
BFR80
BFR88
BFX30
BFX84
BFX85
BFX86
BFX87
BFX88
BFY50
BFY51
BFY52
BRY39
lip
1Op
1468
AF114
AF115
AF116
AF117
AF139
AF239
BC107
8C108B
BC109C
8C147
BC148
8C149
BC157
BC158
BC159
BC189C
80171
BC172
BC173
BC177
BC178
8C179
8C182
BC183
BCY70
14p
41p
39p
39p
18p
13p
12p
14p
32p
14p
12p
17p
24p
32p
20p
24p
108p
70p
38p
43p
74103
pin 14p,
pin 50p
INSULATORS: Mica + 2
Bushes for T03 or T066 Sp
1
AD162
14p
11p
1309
130p
LOW PROFILE OIL
SOCKETS BY TEXAS
1
AD181
12p
BC184
BC187
BC212
8C213
BC214
BC337
BC478
lip
1SSp
FM TUNER
16
AC125
AC126
AC127
AC128
AC176
AC187
AC188
AD149
74191
MULLARD MODULE
LP1186 VARICAP
8
TRAMSISTORS
74191
19p
19p
4012
4013
4016
4017
4018
4020
4022
4023
4024
4025
4026
4027
4028
4029
MULLARD,
322p
88p
155p
C -MOS
4000
4011
RCA, TEXAS, MOTOROLA,
74182
74185
S5p
4002
4007
4009
77p
92p
164p
82p
74162
74163
74184
74166
74174
74175
74177
74177
lip
lip
4001
13Sp
74161
75p
7482
7483
173p
74153
74154
74155
74156
74160
7Sp
7481
7Sp
74151
28p
26p
15p
70p
640
116p
116p
81p
7451
7451
114p
291p
116p
32p
909
32p
52p
73p
75p
75p
81p
70p
74145
74148
74150
lip
7442
7443
7444
7445
7447
7447
7448
43p
81p
70p
74141
30p
33p
40p
39p
7441
alp
48p
74122
74123
74126
74132
74136
lip
7422
7423
7425
7427
7428
7430
7432
7437
7140
7491
74121
65p
32p
12p
15p
43p
7421
103p
130p
32p
291p
43p
7497
74100
74107
74118
Up
Up
7412
7413
7414
7416
7417
7420
7484
7485
7488
7480
7490
7492
7493
7491
7495
7496
22p
PRICES
other extras
Complete kit as illustrated (less betts,)
with a variety of 30 tools. Space for
Stand and Transformer.
30 TOOLS
STAND
TRANSFORMER
KIT
SAE
£16.00
p.p.
£3.70
p.p.
£5 50
p.p.
75p
35p
75p
FOR
DETAILS
Practical Wireless, May 1976
SINCLAIR IC20
IC20 10W + 10W stereo
SINCLAIR BLACK WATCH
PS20
VP20
SP20
strap£20.l5.
Send
IC amplifier kit with free
booklet and printed circuit 16-95.
Power supply kit for the above £495.
Volume, tone-control and preamp kit E795.
10W 4 ohm speaker for IC20 £2.55.
sae for free leaflet.
printed circuit
£155
-
all
DELUXE KIT FOR JC12
Includes extra parts for the pcb and vol, bass and
treble controls for mono version E2211. Stereo model
with balance control E4.95.
JC12 POWER
25V
KIT
tAm P £2 lS.
JC12 PREAMP KITS
Type 1 for magnetic pickups, Nits and tuners. Mono
E155. Stereo £310. Type 2 for ceramic or crystal
pickups. Mono t5p. Stereo £170
SEND SAE FOR FREE LEAFLET ON KITS.
INCLAIR PROJECT N
£125. P25 £315. 016 E10.95. PZ6 E1170.
PZ8 £9.10. Trans for PZ8 £5.40. 240 a.575. Stereo 80
E1185. Project 805. Project 805Q £18IS. Quad decoder
£1485. 260 discontinued but we stock 30W similar
FM tuner
£130.
E3
l5
MAINS TRANSFORMERS
6-0-6V 100mA 95p. 9-0-9V 100mA ISp. 18V
0. 12, 15, 20, 4, 30V 1A E395'. 12-0.12£
6
Switched utp00m 3/41/
Cambridge Memory 411-20.
Scientific Eí95. Oxford 100 £655. Can. St' E1495.
Oxford 300 £16.115. Programmable scientific £2555.
Mains adaptor for programmable and Oxfords £315.
Mains adaptor for Cambridge and Scientific 415.
6/7 }/9/12£ at 500mA with
CBM CALCULATORS'
796MD 4615. 897D P.O.A. SRIS00 P.O.A. 776MD
7 diglt /% /memory £555. SR7919D 8 digit /memory/
trig /log /pi /powers /scientific notation £1320. SR4I4SR
with mains unit E3495. Mains unit for other machines
£295.
6 -WAY
E7.95
4 -way
IA £1.65.
£1
95'.
DOUBLE RADIO MODEL L6110
Similar to above, but with press -stud battery con 3 + 3/41 + 41/6 + 6/71 + 7 1/9
at 250mA. Also gives 15/18/24V single.
nectors.
3 -WAY
with press -stud battery connectors for radios,
etc. 6VE295. 9V £2.55.4} +4}V £445. 6 + 6V E1.45.
9 + 9V &415.
CASSETTE MAINS UNITS
output E run cassette Tcorders from the mains.
Complete t to 5 pin DIN plug rdrS.
regulated £39S'.
Send sae for free leaflet on range.
radio type with press stud battery terminals.
£185.5V E195. 9V E115.
double radio type with press stud terminals.
+ 41V £275. 6V + 6V Et 7S. 9V + 9V £75.
100mA cassette type with 5 pin DIN plug. 7 1V 4195.
Stabilised 11-way type with voltage stabilizer to give
1011mA
41V
SOmA
41V
E715
carriers:-
-r
y/%
di!: plain £1.117
with socket f.221
70 TOS: plain Np, with socket
16
low hum. 3/4 1/6/7 119112(15118£ SOmA E39S.
Heavy duty 12 -way types 41/6/7/8}/11/13/14117/27 /28/
34/42£. tAmp £3 95. 2 Amp £5 95.
Np.
W.
Post 30p on orders under £2, otherwise free. Prices
include VAT. (Overseas customers deduct 7% on
items marked ', otherwise 20 %). Official orders from
schools, government labs, etc. welcome.
SWAN LEY ELECTRONICS
Dept. PW, PO Box 68, Swanley Kent
ALIJE
I111PORTAfT
110TICE
TO ALL
to
BATTERY ELIMINATOR KITS
I
SSN1
Genuine GOLDRING Stylus
0800
£23S
0850
G800 /H
E2-35
G800 /E
STOCKISTS
Vero Electronics Limited are
printing a list of Veroboard
stockists. This list will be dist-
ributed to amateur electronic
constructors throughout the
U K. Whether you purchase
Veroboard from a wholesaler
or direct, please forward your
business name and address
inclusion in this list to:Vero Electronics Limited.
Retail Department
Industrial Estate
Chandler's Ford
for
vero
P.
6 P. 25y
£1.95
E4.42
MICROPHONES
VEROBOARD
12V
SOmA
I
£445
Np. 55W Up.
+
MODEL
CAR CONVERTORS
Input 12V DC. Output 6/71/9V DC
SST7
9/12
RADIO MODELS
AND T -DECS
Special Offer-25p or Np on orders accompanied
by 25p or SOp PB Electronics adverts.
S -DeC £224
T -DeC E405
+
Switched output of 6/71/9V at 250mA with 4 -way
multi -Jack plug and free matching socket E2.15'.
S -DECS
20e.
Practical Wireless, May 1976
?7P
socket £5.00.
HR DIGITAL CLOCK KILT
Includes pcb, mains power supply, attractive case,
0.51n jumbo green display, clock chip, and all other
parts. Displays hours and minutes separated by a
pulsating colon. Kit E1250. Built E1350. Send sae
for free leaflet.
and 9V trans are DC rated, thers are AAC2volts.
Hants S05 3Zß
7/v
multi -jack plug
and free matching
CASIO CALCULATORS'
Personal mini 6 + 6 digits ELK. Pocket
8 digits / %/
const £525. Memory 8R 8 digits /% /memory /const
E925. FX20 E1995. Mains adaptor for all models E395.
IC
Make your own printed circular. Contains etching
dish, 200 s0. Ins. of copper clad board, 1 lb ferric
chloride, etch resist pen, small drill bit, laminate
cutter and instructions.
0.
-WAY SPECIAL
6
SINCLAIR CALCULATORS
u -DeC A
u -DeC B
PRINTED CIRCUIT KIT
model. 3 to 30V in }V steps. Fully
stabilized. IA output. Kit £795. Assembled £1015.
2 Amp model. Kit E995. Built £1253.
24
LOUDSPEAKERS FOR JC12
Bin x 5in 8 Ohms 5W £250.
amp
New switched
Bracelet £2.
Cambridge
JC12 AMPLIFIER
6W IC audio amp
with free data and
BATTERY ELIMINATOR BARGAINS
55 WAY SUPER
Fully assembled
with black
P.
L P. 25p
UD 130 -Cardiold dynamic dual impedance 600 and 50k0
ECM81- Cardiold condenser omni- directional 600 and 50k0
impedance
RX201- Cardiold dynamic 6000 echo mike, 4 transistors. 1-5 sec
reverberation time, with volume control and on-off switch
Philips type cassette mike
Cassette stick mike with remote control
Gem 2 station intercom (baby alarm)
CASSETTES (Low Noise)
1
C60
C90
C120
-5
over
x8'x41"(8 "a5"
or
P. 6 P. 25p
6
P. & P. 25p
250V a.c. 40 watt
7
E1 .30
S2p
SOLDERING IRONS
P.
4140
L P. 85p per pair
"x4 "cutout)
x 71" (10", 8" or 8 "x5 "cutout)
18" x11 "x71'(8" and 3 ",8"x5" or8 "cutout)
22" x14" x71" (13 "x8" or 12" and 3" cutout)
12" x12"
E1-65
E3IS
IOp
12V d.c. 15 watt £1.24
12"
E093
32p
35p
43p
55p
CABINET KITS
£3.58
£199
£2N each
£4.05 each
£5.10 each
E61S each
ALL PRICES INCLUDE VAT
Items subject to availability and manufacturers' increase. U.K. only.
Riversdale Electronics
Mail Order Department PW5
P.O. Box 470, Manchester M60 4BU
87
Do it in your spare time. And enjoy it. And, perhaps, you'll save yourself some money.
The secret is to be practical about the way you spend your spare time.
These practical magazines show you how.
Every month these six popular titles are packed with fascinating and constructive projects -
full instructions for making your own furniture and fitments for the home
as well as electronic gadgets for home, car or hobby.
See which `practical' can widen your range of interests, whether in
home -improvement, hi -fi or electronics - and on jobs you really could call useful.
MODERNISM FM TUNERS
AUTOMATIC WOE SYNCHRONISER
For over 40 years Britain's premier
magazine for the do- it- yourself radio
and electronics constructor. See how
Practical Wireless makes technicalities
crystal clear even to the newcomer.
April issue: 8 -page supplement Fault-Finding Techniques.
OUT MARCH 5
35p
Every aspect of the sound scene is
covered in Practical Hi -Fi & Audio, which
month by month shows you how to choose.
match and improve your equipment. April
issue: 12-page supplement- Buying on a Budget.
OUT MARCH
Be
88
12
30p
Practical...Get a
6
Practical' Today !
please contact:
If you are unable to obtain a copy of any of the above titles from your newsagent,WC2B
5DD.
Sales Manager, IPC Magazines Ltd., 66 Great Queen Street, London
Practical Wireless, May 1976
Practical Wireless Classified Advertisements
The pre -paid rate for classified advertisements is 14p per word (minimum 12 words), box number 35p
extra. Semi -displayed setting £12.00 per single column inch. All cheques, postal orders, etc., to be made
payable to PRACTICAL WIRELESS and crossed "Lloyds Bank Ltd." Treasury notes should always
be sent registered post. Advertisements, together with remittance, should be sent to the GMG Classified
Advertisement Manager, PRACTICAL WIRELESS, IPC Magazines Ltd., Room 2337, King's Reach Tower,
Stamford Street, London SEI 9LS for insertion in the next available issue. (01 -261 5846).
Receivers and Components
COMPONENTS GALORE, pack of 500
assorted Radio, TV and Electronic
components, a real bargain at a realistic price. Send only £1.50 c.w.o. This
applies only to United Kingdom and
Ireland. Overseas prices by arrangement. Caledonian Components. PO
Box 3, Glenrothes, Fife, Scotland.
\\ \
/
ELECTROLYTIC
CAPACITORS
6V
PACK
1
100 PACK
1
50
- 63V
015µF
022µF
0'25µF
033µF
0.47µF
27
33
83
33
33
33
0.68µF 50.8
- 68 MFD
£1
00
£11
.84
PACK
10
-1000 MFD
L1.52
100 PACK
10
-1000 MFD
£2.52
50
All High liability --extremely Low Leakage
4400 AC RANGE
68V DC RANGE
Value
Dimes- Price Value µF
±1 °; ±2q;,
1µF)
lions (um) each 001µF & 0.10, 66p 49p
L
D
022µF: 0330F; 875 50P
01µF 27 12.7 610 047µ1°
67p
50p
06µF
-68
MFD
Small superhet circuit boards
requiring only controls and tuned circuits. 9 volt. Mosfet mixer, IC IF, BFO,
Prod. Det. Excellent AM /CW /SSB
results reported by delighted users.
From £11.50. SAE details. PR Golledge Electronics, Millend, Stone house, Glos.
ules.
Precision Polycarbonate Capacitors
I NIXED
K<O.MINIATURE
5
V1
COMMUNICATIONS RECEIVER mod-
CASH WITH ORDER
PLUS 25% VAT
12.7
16
16
16
19
19
12
(Dept. C)
OAKINGTON AVE
RAYNERS LANE
I
-SµF
19
50-8 19 21'08
50.8 25-4 81.21
50.8 25.4 6144
82p
89p
96p
11.15
11.82
680
82p
71p
75p
92p
11.18
15µF
2'1µF
,
15V /25V or 35V; 100µF at ISV /20V or 25V; 22.Oµ0 at
6V/10V or 16V; 33'0µF at 6V or 10V; 47.OMF at 3V ..r 6V;
1000µF at 3V. ALL at 12p each; 10 for 6110, 50 for
15.00e, ins for 19 00.
TRANSISTORS I' I,C.'s
BC107/8/9
lip
9p 11C212 /212L 14p 213702/4
BCI14
lop ItC213/213L lip 213055
600
BC147 /8 /9 l00 ßL114 /'1147. 11D 0(71/2
12p
ßC.153/154 120
NF.555TImer 810
BF
194/5
12p
BCI57/8/9 12p
741C8pin DII.
BC7821182L lip Ii F'Y5011 /2 200
820
AF178
80p
Z1,7414
1115
ßC184 /184L lop AF234
S8p BN76013Nn1160
POPULAR DIODES-15914 6y, 8 for 46p, 18 tor 905;
151916 Sp. 6 for 465, 14 for 90p, 1844 6p, 11 for 60p,
1184148
34 for 11.00,
Sp, 8 for 57p, 12 for 48p; 1N4001
lip; 002 Op; 008 05p:004
HARROW, MIDDX.
740
8188 11.38
4240 11.95
65.22 5279
20µF
1428 18.138
TANTALUM BEAD CAPACITORS-Value available:
0 1, Oß2, 0.33, 0.47, 0.6
1.0, 2.2, 3.3, 4.7, 681./F at
I SMF
ßC183/1831, Ilp
M.C.L.
590 0680,
64p 1.0µE
67p 15µF
755 2'2µF
80p 3'3µF
87p 47µ1'
98p 08µF
7p; 000 7ip; 006
9p; 007 800
LOW PRICE SERER DIODES- 400mW, Tel. d:6% st
5mA. 3V: 3V3. 2V6; 4V7: IV!: 5V8; 6V2; 6V8; 7V5;
8V2;9VI;10V; 11V; 12V; 13V 13.5V; 15V; 16V: 18V;
20V: 22V; 24V; 27V; 30V; 33V. All at 7p each, 5 for 88p,
10 for 65p, 50 for 8512. SPECIAL OFFER: 100 Zeser,
(may be mixed) for 1800.
RESISTORS -High stability. low noise carbon film 5 %,
IW at 40 °C, iW at 70 °C. Ell series only -from 2-2tì
to 2-2M 1). ALL at
each, 85 for 10 of any one value,
70p for 100 of any o value. SPECIAL PACK: 10 of
each value 2.2 t) to 2.2M Il (730 resistors) e6.
SILICON PLASTIC RECTIFIERS -1.6 amp, wire -ended
D027: 100 P.I.V. 79 (4 for 28p); 400 P.I.V. 8p (4 for SOp).
BRIDGE RECTIFIERS-29 amp: 200V 400; 550V 465;
;
COMPONENTS. Resistors, capacitors, diodes, transistors. pots, coils, etc.
Identified formed leads, fall -out, and
surplus. Good value at £1.60. All inclusive (U.K. postal rates only). CWO
please to L. Penseney, PW Bankhead
Farm, South
Queensferry,
West
Lothian.
500
WENTWORTH
RADIO
IA Wentworth Ct. Alston Road,
Barnet Herts.
TBA520Q
TBA5500
BT106
IN4148
09
95
05
L285
2N3055
4I
LI 80
-80
TIP29C
TIP30C
34
L220
L300
TBA750Q
TBA990Q
L2. IS
R2010B
SN76227N
BC 107/8/9
.46
COMPONENTS-UNITS-VALVES
SEND S.A.E. FOR LISTS
Minimum order 75p. P &P Sp. per item.
Minimum 15p plus 25% V.A.T.
ALL PRICES
SUBJECT TO FLUCTUATION
Practical Wireless, May 1976
ZTX504
10p
10p
10p
10p
10p
10p
14p
BC184L
BC212L
BC213L
lop
BC214L
TO-220
7805 (5V)
L1-59
Ip
7812 (12V)
5p
9p
7815 (15V)
E1-59
L1-59
351800V Rec.
7824 (24V)
15p
49P
BRIDGES
51p
55p
E1;59
1A/200V 26p
2A /600V 33p
D1L 1.C's
741 8 pin 25p
72p
71P42Á
TIP2955
TIP3055
LATORS
4p
4p
1N4007
149
46p
TIP29A
TIP30A
TIP31A
TIP32A
TIP41A
REGU-
25p
40p
39p
4p
2N3005
2N3819
1N914
1N4148
1N4002
1N4003
1N4004
79p
64p
49p
CAPACI.
TORS
IOmfd /12V
10/20p
100 Et
1000mfd /6V
Timer ISp
DISPLAYS
555
TIS43(UJT)
35p
15p
LED 7 -Sep
25p
0375; LI-15
15p 10.5;
E7 ;49
INC. P. and P. at 20p.
data-S.A.E. Please.
ZTX300
ZTX304
ZTX500
V.A.T.
10/30p
1M/E1.50
Display
Tel.: Kingston Blount 52683.
19,
AUDIO. OPTICS
Midoleway, Chinnor, Oxon.
NEW COMPONENTS BY RETURN.
BC109C 12p, BC182L 10p BC184L llp,
BC212L 12p, BC214L 13p, BD529 65p,
BD530 65p BDY56 £1 75, BFR39 35p,
13F1179 35p, 2N5457 45p
2N5459 45p,
MPSA12 40p, MC1310P £ßl'70. Inclusive
prices. P & P IOp. All components
brand new and guaranteed. I. G. Bowman (Dept PW), 59 Fowey Avenue,
Torquay, S. Devon.
POLYESTER CAPS C290 -1 250V 4 tor Sp
BAR
REED SWITCHES Large /Small 10p
MAGNETS 7p ; Large red L.E.D.S. 25p 5 for LI
5 yards CONNECTING WIRE, asstd. colours 10p
;
BURGLAR ALARM 14V DC 75p enamelled.
COPPER WIRE 32, 34, 36 S.W.G. 1p ft.
LOUD 8V D.C. MOTOR DRIVEN SIRENS LI -29
CAPACITORS or RESISTORS Assorted pkt. 25p
Prices include VAT. Add 12p postage.
64
GRIMSBY ELECTRONICS
Tennyson Road, Cleethorpes, Humberside
our Lambert Road Corn-
100's of Bargains at
ponents
shop (open Saturdays). 1978 List 9p.
I5
600V
up.
SUBMINIATURE VERTICAL PRESETS-0-1W only;
All at bp each 50; 100; 220: 470; 680 ohm; 1K; 2K2;
4K7; 6K8; 10K; 15K; 22K. 47K; 100K; 250K; 680K:
1M; 2M5: 55l.
PLEASE ADD 20p POOT AND PACKING ON ALL
ORDERS. EXPORT -ADD COST OF BEA /AIRMAIL.
Add 8% VAT to all items except those marked with
which are 25%
Send S.A.E. for additional stock lists.
Wholesale price lints available to bona Ode companies.
MARCO TRADING (Dept. W5),
Telephones 01- 440 -0409 -01 -441 -2328
FULL SPEC. NEW DEVICES, BY RETURN
BC107
BC108
BC109
BC182L
BC183L
The Old lobool. Ednieston, Nr. Wan, Shropshire.
Tel: Whlssll 484/466 (STD 094 976)
(Props,. Mlnlcost Trading Ltd.)
TRIACS
formers 100mA
£1 50
Quick drying ferric chloride etch
resist ink, applied by pen or brush.
64,
400V/10A
6-0 -6V
85p,
dil ICs
Trans-
12 -0-12V
Electronics,
106
London W7 2LX.
Studley Grange Road,
AERIAL WIRE, HARDWARE,VERO PRODUCTS
Resistors, 4W, IW 5 %, 2ß11-2ßM 1p
Capacitors, all types, from 3p
Denso D.P. Coils, t -5 Green, 74p;
69p; 8-7 B, Y,
1
-5 B, Y, R,
W,
R, 60p
IFT's 13/14/15/18/17, Np. VAT not Included.
full lists.
CLEVELAND SUPPLIES (PW)
P.O. BOX 20, REDCAR
CLEVELAND
P. 6 P. 20p. S.A.E. for
Yes, still the same JUMBO bottle
Beware of imitations
P.C.B. Ink
TAG250
2N3055 36p, 300W Dimmer Kit
£1.95. P &P 15p. Add 8% VAT. T. K.
95p
-
175cc
(Plastic)
67p (3 +64p); Diacs 19p, 8 -pin
741 24p, 555 44p, Mini Mains
MAWSON ASSOC.
Brookbank Road, London SE
13
METAL BOXES /INSTRUMENT
CASES. Range of over 100 standard
sizes with punched holes to your sped fication if required. B.M.S. cut to size.
Components. Audio equipment, kits
and complete. 2 x 6'2p stamps for
lists. Nottingham Audio Services, 13/
15, Foxhall Road, Nottingham NG7
6NA.
89
COMPONENTS
BRAND NEW
Electrolytics-16V,
RETURN:
BY
Service Sheets
25V,
50V -0.47, 1 0, 2 2, 4 7, 10 mfds.1005p. 22, 47 -511 p. (50V-6p)
7p
(50V -8p), 220 -8p. (WV-10p),
500-11p. (50V -16p), 1000 /25V-18p.
Service Sheets for Black and White TV, Radios, Record Players and Tape Recorders 50p.
Please send large Stamped Addressed Envelope.
We can supply manuals for most makes of Colour Television Recievers.
B.R.C. PYE ECKO PHILIPS ITT! KB SONY G.E.C. HITACHI BAIRD ULTRA INVICTA etc.
Please send a Stamped Addressed Envelope fora prompt reply.
2.2/35V, 4.7/35V, 10 /20V, 22/16V, 47/
6V, 100/3V.-11p. Mylar Film 100V.0 001, 0.002, 0.005, 0.01, 0.02. -3p.
0.04, 0.05-3,2 p. Mollard tubular
polyester 400V E6 series 0.001-0.022312 P. 0.033- 0.1 -412 p. Mullard miniature C333 ceramics 63V E12 series 2 %,
1.8 pf. -47 pf.-3p. 56 pf. -330 pf. -3'2 p
Polystyrene 63V E12 series 10 pf. -1000
pf. -3p. 1200 pf.- 10,000 pf-4p. Miniature Highstab. carbon film resistors
h3 W E12 series 5% 1t?- lOM!l. (10% over
IMt)) 1.2p. Postage 10p, Prices VAT
Inclusive. The C.R. Supply Co., 127,
Chesterfield Road, Sheffield S8.
Educational
GO TO SEA as a Radio Officer. Write:
Principal, Nautical College, Broadwater,
Fleetwood FY7 81Z.
C
AND
G
EXAMS
Make sure you succeed with an ICS home study
course for C and G Electrical Installation Work &
Technicians Radio /TV/Electronics Technicians,
Telecomms Technicians and Radio Amateurs.
COLOUR TV SERVICING
Make the most of the current boom! Learn the
techniques of servicing Colour and Mono TV sets
through new home study courses, approved by
leading manufacturers.
TECHNICAL TRAINING
Home study courses In Electronics and Electrical
Engineering, Maintenance, Radio, TV, Audio,
Computer Engineering and Programming. Also
self -build radio kits. Get the qualifications you
need to succeed.
Free details from:
INTERNATIONAL
CORRESPONDENCE SCHOOLS,
Dept. 7785, Interject House, London SWI4UJ.
Or Phone 91.622 9911 (Ait Hoses)
MANCHESTER EDUCATION COMMITTEE. Tenders are invited for the purchase of second -hand audio -visual aids
equipment. Further details and forms
of tender from Supplies Officer, Stores
Department, New Cross, Manchester,
M4 5ES, returnable by 10th May, 1976.
TAPETALK
THE NATURAL WAY TO LEARN
- COLOUR TV MANUALS
SERVICE SHEETS
bead-type tantalums
-0.1/35V, 0-22/35V, 0.47/35V, 1-0/35V,
Subminiature
G.
10
T. TECHNICAL INFORMATION SERVICE
DRYDEN CHAMBERS,
119 OXFORD
MAIL ORDER ONLY
LARGE SUPPLIER
OF
SERVICE SHEETS
SERVICE SHEETS for Radio, TV,
Tape Recorders, Stereo, etc., with free
fault-finding guide, 50p and SAE,
Hamilton Radio, 47 Bohemia Road, St.
Leonards, Sussex.
(T.V., RADIO, TAPE RECORDERS,
RECORD PLAYERS, TRANSISTORS,
STEREOGRAMS, RADIOGRAMS,
CAR RADIOS)
For Sale
ALL AT 50e EACH
"
PLEASE ENCLOSE LARGE S.A.E
WITH ALL ENQUIRIES & ORDERS"
Otherwise cannot be attended to
(Uncroed P.O.s pleam original
returned II service sheets not available.)
PLEASE NOTE
We operate "by return of post" service. Any
claims for non -delivery should be mad. within
7
of posting your order.
-dy
C.
CARANNA
BEAUFORT PARK
LONDON, N.W.11 6BX
We have the largest supplies of Service
Sheets (strictly by return of post). Please
71
state make and model number alternative.
Free TV fault tracing chart or TV list on
request with order.
Mall order or phone 01 -458 4882
Large Stocks of Colour Manuals
NO OVERSEAS MAIL PLEASE
Best! Cheapest! ReBumper catalogue: Aarvak
Electronics, 12a(P) Bruce Grove, N17
DISCOLIGHTS.
liable!
6RA. 01-808 8923.
MICROPHONES: AKG D202EI, £4500;
AKG D190C or E, £2000; AKG D224,
£6000; Sennheiser MD211N, £45.00. All
brand new and boxed. Please add 25%
for VAT. All other AKG and Senn -
heiser mikes, SAE for quote. J. J.
Francis (Wood Green), Ltd., Manwood
House, Matching Green,
Harlow,
Essex. Tel: Matching 476.
COPPER CLAD LAMINATE
FOR
PRINTED CIRCUITS
-I -5p /sq. Inch.
Single sided 1/16" paper base
Single sided 1/16" glass- epoxy-2'0p /sq. Inch.
Any rectangular cues cut to your requirements.
Please send cash with order.
Price includes postage and pecking.
From: SIMTECH ENGINEERING LTD
Dedham Road, Ardletgh, Colchester,
COO 70A
Telephone 0208
Essex,
SHEETS, radio, TV etc.
10,000 models. Catalogue 24p. plus SAE
with orders, enquiries. Telray, 154
Brook Street, Preston Plu 7HP.
SERVICE
BELL'S TELEVISION SERVICES for
service sheets, manuals & books on
radio /TV etc. Service sheets 50p plus
SAE. Service sheet catalogue 25p.
Back issues of magazines from April
'74 onwards cover price plus 12p post.
Free booklists on request. SAE with
enquiries please to B.T.S., 190 Kings
Road, Harrogate, Yorkshire. Telephone Harrogate (code 0423) 55885.
FOR SALE: Codar AT5 +AC PU, £20.
Deliver Tyne Wear, Nesbitt, 34 West
Dene Drive, North Shields.
Wanted
WE BUY New Valves, Transistors and
clean new components, large or small
quantities, all details, quotation by
Tape Recorders
and TRANSISTORS
poplar T.V. end Radio types.
KENSINGTON SUPPLIES (C).
Kensington Street, Bradford 8,
Yorkshire.
FOR HIRE
Electrical
Over 3,000 titles to chose from, for as little as
no per day. Many special benefits to members.
Free brochure from:
STYLI & CARTRIDGES. For the best
at keenest prices send SAE for free
illustrated list to FeLstead Electronics
(PW), Longley Lane, Gatley, Ches.
SK8 4EE.
THE STEREO CASSETTE LENDING
LIBRARY, Room 10, SHERWOOD HOUSE,
SIMMONDS ROAD, CANTERBURY CTI 3RL
TAPETALK
LADDERS. Varnished. 2512 ft extended,
£2405, carriage £1.40. Leaflet, alu-
minium ladders and loft stairways.
Tel: Telford 586644.
90
361
PCR.3 Receiver Coils and
will buy complete if items
intact and good condition.
nan, 29 Elmfield Street,
Manchester
THE CLEVER WAY TO LEARN
TWO C60 Cassettes entitled
INTRODUCING ELECTRONICS
' £5.44 plus
55p VAT /P. & P.
TAPETALK, P.O. Box 99 (PW)
Milton Keynes MK3 5BR
Tel.: Milton Keynes (0908) 77710
Worcester
TOP PRICES PAID for NEW VALVES
M USICASSETTES
Ladders
230133
return. WALTON'S. 55
Street, Wolverhampton.
Two C60 cassettes entitled
THE SCIENCE OF SOLDERING
£5.44 plus 55p VAT /P. & P.
TAPETALK, P.O. Box 99 (PW)
Milton Keynes MK3 5BR
Tel.: Milton Keynes (0008) 77710
ST., LONDON WIR IPA
8.
dialglass or
wanted are
A. J. Bren-
Cheetham,
REASONABLE price paid pre -1960
P.W's. Details and price please. Box
130.
WANTED EX- GOVERNMENT TR1936,
I.F. Strips 10U/254 and Parts Manuals
Radio /Radar 10A, 10B etc. B.H.
Avionics Ltd., Biggin Hill Aerodrome,
Kent, Tel No. B.H. 71465.
Practical Wireless, May 1976
Miscellaneous
BUILD
THE
fp
MK III
2 -3 Cape, £3.50. Pack 5
8 Pote, £150. Peck 7
Semi Conductors, £025, P.C. Board £300.
Front Panel £2.50, Chassis £3.00, Case £3'50,
p.p. extra 25p except chassis Sep and case £1.00.
Tax extra 25 %. Send S.A.E. for details of this
and other amplifiers from 1 watt-100 watt.
Pack
Vàr,cap tuning
Res, 80p, Packs
325,
TELERADIO ELECTRONICS
FORE STREET, LONDON, N.9.
01. 807.3719
J
envelope for leaflet
Complete
Built 6 tested £,17.50
Kit
Post 85p £1110 VAT 8% Post 85p £140 VAT 0%
MINIKITS ELECTRONICS.
6a CLEVELAND ROAD.
LONDON, EIS 2AN
(Mail order only)
£12.50
1
275a
Switches £150. Pack
Metal locator
Britain's best selling metal
locator kit; 4,000 sold
Weighs only 220e. Fitted with
Faraday shield.
Speaker and earphone operation
Knocks down to only 171n.
Prebuilt search colt assembly
Thoroughly professional finish
As seen on BBC1 and BBC2 TV
You only need soldering Iron,
screwdriver, pliers and snips
Five transistor circuit
Send stamped, add
d
H. M. ELECTRONICS
TEXAN AMPLIFIER PARTS
TREASURE TRACER
COLCHESTER COMPONENTS SHOP.
Now open Sunday-Thursday 12 -6 p.m.
J. K. Electronics, 11 Mersea Road,
Colchester
64433.
FULWOOD ROAD, BROOMHILL,
SHEFFIELD S10, 3BD.
BEC. CABINETS (Illue'd)
METAL CASES
DRY TRANSFER LETTERING
Send 15p for leaflets (Refundable)
Trade enquiries Invited
NICKEL CADMIUM fully sealed rechargeable batteries. Equivalent dry
cell sizes. Discount. S.A.E. brings full
details by return. Charges available.
Sandwell Plant Ltd. , 1 Denholm Road
Sutton Coldfield, West Midlands, B73
6PP. 021 -354 9764.
P
TRANSMIT!
TRANSMITTER /RE* Unique
CEIVER
THE SCIENTIFIC WIRE CO
Copper
-
Nickel Chrome
-
Wires.
*
Eureka - Menganln
Enamelled - Silk - Cotton - Tinned Coverings.
No minimum charges or quantities.
Trade and Export enquiries welcome.
S.A.E. Brings List,
P.O. BOX
30,
LONDON, 54 $BW
Kit. No licence examinations or tests required to operate
this transistorised equipment. Easy
to build. Get transmitting. Send
£7.95 for yours now!
Psychedelic MINI- STROBE Kit.
Take a pocket -sized lightning storm
to Disco's & parties. 'Brain -f
'
'em with vari -speed stop -motion
flashes. Includes super cue too.
Send £3.50 now!
(all prices include V.A.T., packing
& postage.)
Send
SUPERB INSTRUMENT CASES by
Bazelli, manufactured from heavy duty
PVC faced steel. Hundreds of people
and industrial users are choosing the
cases they require from our vast
range, competitive prices start at a
low 75p. Examples: width, depth,
height, Bin x 5in x 3in, £1.55; loin x bin
x 3in, £2.20; 12in x bin x 3in, £2.70;
14in x bin x 3in, £2.95; loin x Bin x 3in,
£2.75; 12in x Sin x 3in, £3.20; 14in x 8in
x 3in, £3.60; 12in x loin x 3in, £3.60;
8in x 4in x 4in £1.80; lain x 6in x 4M,
£2.70; 12in x bin x 4in, £2.85; 14in x
bin x 4in, £3.25; 12in x 8in x 4in, £3.60;
14i1v x Bin x 4in, £3-80; 7in x 7in x Sin,
£2.65; 8in x loin x bin, £3.60; 12in x 8in
x 7in, £4.00; 14in x 8in x 7in, £4.80;
12in x loin x 7in, £4.25; 12in x 12in x
7in, £4.40; 14in x loin x 7in, £5.00; 12in
x loin x 8in, £5.00; 14in x loin x 8in,
£5.30; 14in x 12in x 7in, £5.20; I2in x
12in x Sin, £5.50; 14ín x 12in x 8in,
£5.80. Plus 72p carriage and 8% VAT.
16in x 8in x 8in, £7.60; 16in x ldin x
8in, £8.40; 18in x 8in x 8in, £9.50; I8in
x loin x 8in, £10.30; 1914in x 8in x 8in,
£11.50; 1914 in x loin x 8in, £12.30.
Plus carriage £1.25 plus 8% VAT. Over
models. to choose from. Prompt
despatch. Free literature (stamp would
be appreciated), Bazelli, Dept. No. 25,
St. Wilfrid's, Foundry Lane, Halton,
Lancaster LA2 6LT.
400
ENAMELLED COPPER WIRE
S.W.G.
lb reel
} lb reel
10 to 19
2.40
1.35
20 to 29
2.45
1.40
1
to
34
2.60
1.50
to 40
2.85
1.60
All the above prices are inclusive of postage
and packing in U.K.
30
35
COPPER SUPPLIES
102 Parrswood Road, Withington,
Manchester 20
Tel: 061 -445 8753
DO -IT-YOURSELF loudspeakers for hifi are our speciality. Full range of
components and accessories including chassis speakers, crossovers, sound
absorbent, grille fabrics etc. always
available. We stock the fabulous
value Helme speaker kits complete
with full and easy instructions, also
Peerless and Wharfedale kits. Just
about the lowest prices anywhere!
Send 81-,p stamp for bargain list to:
Audioscan, Dept. PW575, 4 Princes
Square, Harrogate, North Yorkshire.
Practical Wireless, May 1976
remittance to:
BOFFIN PROJECTS,
Make SOUND
RECORDINGS
from a TV
set using
this
ADAPTOR
/
your
cassette recorder.
or use it with your
Hi -Fr or headphones. Completely Safe,
Fully Isolated. Leads. connectors and full
instructions included. £6 inc post and VAT
or write for leaflet.
i
d'ROWBOROUGH ELECTRONICS
(PW) E.,dge Road, Crowborough,
Sussex
CUNLIFFE ROAD,
STONELEIGH, EWELL, SURREY
4
(Mail order U.K. only)
Or for more details, send 20p for lists
NOTCH OUT QRM!
Tunable Audio Notch Filter rejects hetrodyne
and CW interference FAST. Goes between RX
and speaker. EASY TO MAKE. All parts, case,
instructions, money back assurance, ONLY £5.30
poet free
45
CAMBRIDGE KITS
(Box E), Old School Lane, Milton,
Cambridge.
PACKS of assorted
copper
laminates for 60p plus p/p 30p. Cash
with order to Crossley & Bradley, 248
Slater Lane, Leyland, Lancs.
1LB
PRINTED CIRCUITS
and HARDWARE
Readily
12 VOLT 21" 13 Watt Fluorescent Lighting
(by Thorn /AEI) with diffuser A on/off switch. Ideal
caravan ,boa,, emergency Iluhtino.etc. Guaranteed.
L3.50
Inc. VAT
&
Post. List price £7 02 Inc. VAT
SALOP ELECTRONICS
Shrewsbury, Shropshire
23
Wyle Cop,
Tel. 53280
ALUMINIUM SHEET AND BOXES cut
and folded to your design. Sheet: 22,
20, 18 S.W.G. 0.5p /sq inch; 16, 14
S.W.G. 1p /sq inch. Boxes: 22, 20, 18
S.W.G. 1p/sq inch; 16 S.W.G. 112P /sq
inch; 14 S.W.G. 2p /sq inch. Maximum
length of any side: 2ft. Maximum
depth of box: 1 ft. Please add 8% VAT.
P &P 25p per item. SAE for special
quotes (UK only). Trade enquiries
welcomed. Simtec Electronics (UK)
Ltd., Unit 37, Faircharm Trading
Estate, St. Mary's Mills, Leicester. Tel:
available supplies of Constructors' hardware, Aluminium sheet
and sections. Printed circuit boards,
top quality for Individual or published
designs. Prompt service. Send 15p for
catalogue.
Ramar Constructor Services,
Masons Road, Stratford on Avon,
Warwicks.
Tel.
4879
GLASS FIBRE P.C.B.s. Send 1:1 master
and 7p per square inch tinned or 9p
per square inch drilled and tinned
PLUS 30p per board. Send for quotation on double sided boards. Discount
for quantity. PROTO DESIGN 4 High
cliffe Way, Wickford, Essex SS11 8LA.
(0533) 824380.
DO -IT- YOURSELF
MINI
ACCUMULATORS
2
volt MULTI - USE
Sealed Lead Acid Rechargeable Cells.
Size L450 -14" X 1.1"
X
44". 3 for £2.15
inc. P. & P.
Siva 0A2 -17" X 1.3"
X
.5 ". 3
for £265
Ina
GARFIELOS,
295
P. & P.
Suits FI -Cord
Rye Lane, London,
S.E.IS
HI -FI STEREO
SPEAKER KITS
The best value around!
Send for details
HELME AUDIO
PRODUCTS LTD.
Delrt. Pw
SUMMERBRIDGE
HARROGATE YORKS
TPI: Daeley,279(Std Code 0423.72 )
91
Technical BooksRad io h Electronics
BUILD YOUR OWN
You are invited to send S.A.E. for lists of our
very extensive range of high quality amplifier,
pre -amps, F.M. tuners, instruments. Radiocontrol
Ignition units and many other kits. Please state
Synthesiser
"Sounds
Supreme'"
requirements.
325
TELERADIO ELECTRONICS,
FORE STREET, EDMONTON,
LONDON N9
RADIO. Learn from the beginning.
by Dewtron
16
vintage circuit diagrams, receivers and
transmitters with notes. £1. Allister,
58 Wavell Road, Maidenhead, Berks,
(25
VAT
extra.)
Famous kits. e.g. waa -waa complete
Fuzz kit £6.50 P &P 25P
under £ 10. Ring Modulator modules
£ 11. "Mister Bassman" Bass Pedal
Units and whole range of synthesiser
modules, musical novelties, etc. Catalogue 20p from D.E.W. Ltd., 254
Ringwood Road. Ferndown, Dorset.
kit £4.50;
SL6 5AD.
THE P.E. 'VARICAP'
STEREO PUSH SUTTON
TUNER
.
Books and Publications
T.V. REPAIRS MADE EASY
easy to follow repair manuals cover the mono
3 cover the colour sets from the early
dual standards to date.
Priced at only E3.50 each, you just send make/
model no. (chassis type If possible plus cost to
receive manual covering the set by return. P & P
50p up to 3, £1 over 3.
British Colour T.V. Circuit Diagram Manuals
in 2 vols. cross referenced to the above repair
manuals at E$50 (p. & p. £1) each. All mono
sets circuits in 1 huge manual for same price.
4
Using the latest Mullard modules for R.F. and
I.F. circuits-pre- aligned for ease of construction -this KIT has an F.M. tuner with
stereo decoder, push button tuning, self
regulated power supply, etc., etc., for highest
quality reproduction.
Price £43.50
inc. V.A.T. P &P
S.A.E. for FREE brochure
We also still supply ALL components for the
P.E. 'GEMINI' STEREO AMPLIFIER. Send
55p + 12p P&P fora full constructional booklet
containing performance details, specification
assembly Instruction and fault finding guide.
sets and
T.V. TECHNIC, 76 CHURCH ST., LARKHALL
LANARKS ML01HE
Tel. (0080) 083334.
World's Radio & TV STations (International EdiL)
E0 -70
WORLD RADIO TV HANDBOOK 1976
(Incorporating Row to loon to the Wodd)
L5 -00
Boys Book of Crystal Sets
E0 -35
Television Timebase Circuits
f1 -20
Radio TV and Industrial Tube & Valve Equa
EO --70
How to get the best out of your Tape Recorder
Practical Electronic Science Projects
ÉÚ-85
Jack Dan's Service Clinic
Eí-60
Transistor Circuits for Modern Test Equipment
Modern Tape Recording Handbook
ÉÓ-85
1st Book of Transistor Equiv. and Substitutes
LU -50
Hi Fi, PA & Disco Amplifier Design Handbook
£O -87
Radio Servicing Problems
£0 -75
Electronic Circuits for the Amat Photographer
52 Projects using IC 741 or Equivs
ÉÓ-85
TV Fault Finding
£1 -15
Transis Circuits for Rad. Control'd Models
£0 -50
Practical Stereo & Ouedrophony Handbook
ED -85
Radio Amateur Operator's Handbook
Coil Design & Construction Manual
E0 -60
Radio TV & Electronics Data Book
£0 -70
79 Electronic Novelty Circuits
EC 85
The Complete Car Radio Manual
E0 85
Radio Technicians Bench Manual
f3 -40
Servicing Transistor Radio Receivers
£0 -95
1st Book of Hi Fi Loudspeaker Enclosures
ED 70
2nd Book of Hi Fi Loudspeaker Enclosures
E0 -70
Manual of Electronic Circuits for the Home
EO-60
Modern Crystal Set Circuits for Beginners ..
E0 -455
Electronic Novelties for the Motorist
f0-60
2nd Book of Transistor Equiv. & Substituas
Et -10
Handbook of Electronic Musical Novelties
L0-60
Transistorised Novelties for Hi Fi Enthusiast
£0 -45
Fault Location Exercises in Rad. & TV Vol. 1
E1 -00
Fault Location Exercises in Rad. & TV Vol. 2
£1-60
Colon, TV Picture Faults
E2-80
Practical Transistor Novelty Circuits
£0 -50
Boys Book of Practical Radio & Electronics
E0 -70
Radio Receiver Construction using ICs & Transis
CO-TO
ICs & Transistor Gadgets Construction Handbook
ET -70
Integrated Circuits Equiv. & Substituas Handbook
£0 -85
Audio Technicians Bench Manual ..
£3 -40
Radio Antenna Handbook for Long Dist. Recepa.
ED-90
Guide to Printed Circuits
E3 -40
Diode Characteristics Equv & Substitutes
£1 -.10
Electronic Gadgets & Games
E0 90
PRICES INCL. POST & PACKING
Send S.A.E for List,
....
RADIO BOOK SERVICE
40EIwill Way, Beckenham BR3 2R2
START YOUR OWN BUSINESS
REWINDING ELECTRIC MOTORS
ELECTRO SPARES
Dept. P.W.
Ecclesall Road, Sheffield, 811 IPE
LOW -COST I.C. MOUNTING for any
size DIL package. 100 Soldercon
sockets 60p. 7 and 8 hole plastic
supports 5p /pair. Quantity rates. SAE
details and sample. Trial pack 60p.
(P & P 10p /order). P.K.G. Electronics,
Oak Lodge, Tansley, Derbyshire DE4
5FE.
ORDER FORM
Cassettes
This unique Instruction manual shows step by
step how to rewind motors, working part or full
time, without previous experience. Everything
you need to know easily explained, including
where to obtain materials, how to get all the work
you need, etc. A goldmine of information and
knowledge.
Only E3-65 plus 25p
P &P.
LOW PRICE
ALPHA
C60
POSTAL SERVICE
COMPACT CASSETTES
- 35p
C90
-
45p
C120
-
SSp
Professional Quality.
Low noise.
Minimum 16p. Maximum
Post 4p each.
Magnum Publications Dept PW5
Brinksway Trading Estate, Brinksway,
Stockport 51(3 OBZ.
Overseas Distributors wanted.
Np.
Cambridge Technical Developments Ltd.
i
Seymour Street, Cambridge
PLEASE WRITE IN BLOCK CAPITALS
Please insert the advertisement below in the next available issue of Practical Wireless for
insertions. I enclose Cheque /P.O. for £
(Cheques and Postal Orders should be crossed Lloyds Bank Ltd. and made payable to Practical Wireless).
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ADDRESS
Send to
Classified Advertisement Manager
PRACTICAL WIRELESS, GMG, Room 2337,
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Rate
14p per word, minimum 12 words. Box No. 35p extra.
Company registered in England. Registered No. 53626. Registered office: Tower House, 8/14 Southampton Street, London WC2E 90X.
92
Practical Wireless, May 1976
U.S.A. Govt. Electronics Engr. (retd.), W70E claims "VFA 5ft below ground, same as dipole, elevated 15ft., one
point UP on dipole."
IT'S THE
ABOVE ALL
"S"
MAANTDTERRES
ATRANSMITTING
CEIVING
ensures FURTHER MINIMUM SIGNAL LOSS
MINIMUM RF LOSS and VERY LOW ANGLE FIRE
from Ionosphere and Earth Bounce, making DX- COMMONPLACE-with only MILLIWATTS of
RF
power, in
spite of the present Sunspot minima. Send stamp for PROOF!
-
--
-
-
and S.W.L's, remember, the SAME antenna* is used
YOU just CANNOT AFFORD R.F. LOSSES
IF YOU CAN'T HEAR 'EM ! !
for RECEIVING the DX
YOU SURE CAN'T WORK 'EM
the *JOYSTICK V.F.A.
the 'QRP ANTENNA (230cm -7' 6") that handles ALL your R.F.
"FLEA
POWER" or KILOWATT- EFFICIENTLY ! ! !
AS SUPPLIED
-
TO H.M. GOVT. COMMUNICATIONS H.Q.
-
PRICES INCLUDE V.A.T. INSURANCE AND DELIVERY BY POST OR CARRIER
A.T.U's:- III (Med. wave - 30 MHz), £18.00; 11IA (I 6-30 MHz), £18.00; I I IB (L match,
1.6-30 MHz), £16.20; LO -Z500 (1-8 thru 30 MHz, 500w), £23.35; "RC" (pre- production prototype "impossible" location A.T.U. -S.W. bands)
19.56; BUDGET LINE: A.T.U. I 6-30 MHz, £8.90; A.T.U. Medium and S.W. bands, £8.90 (both in kit form, E7.40); Aerial Bandswitch
(complete aerial system, medium and SW bands), E7.40; Artificial Earth, 17.40; DX CRYSTAL SET (Home and World -Wide reception)
ready to use, 14.86; Comm. Headphones 8 ohm, £4.90; Field Strength Meter, E2 I I; Set valves 9R59DS, £6.21; Coaxial cable 50 or 75 ohms,
per 10 metres, Ef 55; SYSTEM "A ": VFA + I I IB, £32.96; SYSTEM "X ": VFA + either I I or I I IA, 13447; SYSTEM "D ": VFA +
Aerial B'switch, 124.63; SYSTEM "J ": VFA + LO-Z500 + F/S meter, £41.03; SYSTEM "RC ": VFA + "RC ", 127.56.
JOYSTICK V.F.A., 118.00; JOYMATCH
1
PARTRIDGE SUPER PACKAGE
Send stamp
BOX 5
for details and expert advice.
COMPLET E RADIO STATION FOR ANY
LOCATION. Comprising: Trio QR666 Gen.
Cov. RX, Headphones VFA., System "A ", all
Phone
puribegra,°
£20613
connecting cables, del. (our risk). ASSEMBLED
IN SECONDS!
SAVE 014.05.
Just telephone your card number
62535
0843
(or 62839
after office hours)
Buy it with Access
G3VFA
G3CED
FREE
SHORT -WAVE
Brochure
on New
KITS
WORLD -WIDE RECEPTION
KITS
Whether
professional
student, teacher
or
150
Pease send 10 12
stamp addressed envelope
amateur the field
of electlooics can open
up a new world for you
tion problems with this
system (1 muter and
robust plastic cabinets for desk or wall
mounting. Call/talk /listen from Master to Subs and
Subs to Muter. Ideally suitable for Business, Surgery, Schools, Hospitals and Office. Operates
on one 9V battery. On /off switch. Volume control
Complete with 3 connecting wires each 66ít. and
other accessories. P. R P. 75p.
4- Station Transistor Ioteeeom
3 Bobs), in
MAINS INTERCOM NEW MODEL
CROFTON don't lust sell kits. we offer yeas a techwcal
back ,p service to insure your success
-oar
The following is a select an of some of the more
Fanions i,r
,e rn for Short -Wave Equipment of quality. t "H.A.C." were the Original
suppliers of Short -Wave Receiver Kits for the
amateur
Mullard CCTV Camera
PE CCTV Camera
'Mistral' Digital Clock Kit £12.50
incl. VAT. p. & p. 50p. Made up
£1800 incl. VAT. p. & p. 50p
Electronic Ignition
Sound Operated Flash
PW Tele- Tennis Game
UHF Modulator
Bench Power Supply
Wobbulator
All ETI Top Projects
Many of the Elektor Projects
constructor.
Over 10,000 satisfied
customers- Including Technical Colleges, Hospital', Public Schools, R.A.F., Army, Rams, etc.
1876 "DE" RECEIVER
Complete kit- -Price £800 (incl. p. & p. A V.A.T.).
Customer writes:
think the performance is
astonishing for such an inexpensive and foolproof
kit. I would wholeheartedly recommend thin kit
to anyone, however inexperienced, an an antidote
to TV -itis, and as an entry into a fascinating
'I
hobby ".
This kit is ready to aese,oble and contains all
genuine short -wave components, drilled chassis,
valve, accessories and full instructions. Full range
of other S.W. kits, Including the famous model
"K plus" (illustrated above). All orders despatched
within 7 days. Send now for free descriptive
catalogue of kits and components.
Send stamped envelope for details.
"H.A.C."
P.O. BOX
SHORT-WAVE
potala, kits
NOTE
PCBs tw most published protects available
lo order
CROFTON ELECTRONICS LTD
PRODUCTS
No. 16, EAST GRINSTEAD,
SUSSEX RHI9 3SN
Practical Wireless, May /976
Oepl. B,
Grosvenor Road, Twickenham,
Middy. Tele. M -891 1923
35
No batteries -no wires-
Just plug in the mains
for Instant two -way, loud and olear communication.
On off switch and volume control. Price 181.24
per pair P. 0 P. 75p.
NEW,
AMERICAN TYPE CRADLE
TELEPHONE AMPLIFIER
Latest traa.iatorised Telephone Amplifier with
detached plug -in speaker. Placing the receiver on
to the cradle activates a switch for Immediate
two-way conversation without holding the handset.
Many people can listen at a time. Increase efficiency
in office, chop, workshop. Perfect for "conference"
calls: leaves the user's hands free to make notes,
consult files. No long waiting, save. time with
long -distance calls. On /Off ewitch, volume. Direct
tape recording model at 813.86 + VAT L112
P. & P. 70p, 10 -day price refund guarantee.
WEST LONDON DIRECT BDPPLIEB (PWS )
169 KENSINGTON HIGH STREET, LONDON, W6
y
TRANSISTORS
AC12S
AC126
AC127
AC128
AC141
AC142
AC176
WATFORD ELECTRONICS
33j35, CARDIFF ROAD, WATFORD HERTS, ENGLAND
MAIL ORDER, CALLERS WELCOME. Tel. Watford 37774
ALL DEVICES BRAND NEW AND FULLY GUARANTEED.
ORDERS DESPATCHED BY RETURN OF POST. TERMS OF
BUSINESS: CASH /CHEQUE/P.O.s OR BANKERS DRAFT
WITH ORDER. GOVERNMENT AND EDUCATIONAL
INSTITUTIONS OFFICIAL ORDERS ACCEPTED. TRADE
AND EXPORT INQUIRY WELCOME. P & P ADD 25p* TO
ALL ORDERS UNDER E10-00. OVERSEAS ORDERS POSTAGE
AT COST, AIRSURFACE. (SEND 259 FOR OUR CATALOGUE).
1000pF/350V
CAPACITORS
Op
8, 10, 15,
33, 100, Sp;
1
-0, Op; 220, 1SP; 1000, 42p; 40V:
22, Sp; 32, 47, 68, 10p; 100, 12p; S0V :
470, 22p; 2200 40p; 35V: 1000, 30p; 30V: 3500, 41p; 25V: 8,10, 22, 40 6P; 80, 100.160 Sp;
16V: 10, 40,
220, 13p; 470, 17p; 840, 21p; 1000, 27p; 2200, 34p; 3000, 39p; 4700, 47p;
10V: 4, 100, Sp; 640, 10p; 1000, 149;
125, 250, 610; 470, 11p; 1000, 1500, 18p; 4700, 469;
1
TAO -END TYPE:
2200, 18p.
23V: 4700, 41p; 1SV: 4700, 319.
70V:
2500, 911p; 4700, 111p;
38V: 0.1pF, 0.22, 0.33, 0.47, 0.68, 1.0,
2ßuF, 3.3, 4 7, 6.8. 25V: -5, 10
16V: 101íF, 22. 10V: 15uF, 33. SV:47p.F.
Linear values
1
Single gang
17P
17p
5KO -2MO single gang
5K0-2M0 single gang D/P switch 37p
50p
5KO -2MO dual gang stereo
1K SI (LIN. ONLY)
3V: 100uF.
Price: 11p each.
MYLAR FILM CAPACITORS
100V: 0001, 0.002, 0005, 0.019F
0015, 0.02, 0.04, 0.05uF, 0 1aF
0.15, 0250V: 0.47pF
SLIDER POTENTIOMETERS
0.25W log and linear values 60mm
5KO -500KO single gang
4p
Sp
10K0 -500KO Dual gang
50KO Lin 150mm WS 150
6p
CERAMIC CAPACITORS
JACKSONS VARIABLE CAPS.
66p
95p
100 /3039F
500pF
'D'
speed
2
Drive unit cornpiste with knobs
& coupling 322p
6:1 Bell Drive
17p
4511 /DAF
Drum 54mm 30p
00 200/170
240p
2411p
240p
with slow
motion drv. 250p
C8045, 10,15.20,
25
100,
50pF
120p
SOpF 19Sp
'L'
3 310pF 3729
323p
00-3x2SpF
40p
$2p
23.00
PRESET POTENTIOMETERS
0.1W 500 -2.5MO Sub Mln Vert. onlylp
7p
O-25W 1000 -3.3MO Horizontal
7p
0.25W 2000 -4.7MO Vertical
50V d.c. Plaquette body 25mm leads.
Sp
Range: 0.5pF to 10,000pF
dp
0.015uf, 0.022uí, 0.033u0, 0047uí
Dielectric
RESISTORS -Erie make
Carbon, Miniature, High Stability, Low Noise
-99 100+
POWER Toi. RANGE
Val.
5%
2.20 -4.7M E24 1p
0-Sp
0.25W
5%
2.20 -4.7M E12 1p
0.5W
O.Op
1W
2.20 -10M E12 3p
5%
2p
1
100
off price per value not mixed.
CERAMIC TRIMMER HEAT SINKS
CAPACITORS
Sp
T05 /5F
4 -15pF; 6-26pF;
2-79F;
8-30pF 17p each
TO10/10F
Sp
1Sp
1SP
Sp
T086/TV2
MINIATURE
T03/TV3
3-30pF; t0-4'pFF Insulation Kit
3(Mica & 2 washers)
34P
ION
COOS
SOCKETS
Low profile
27p 8 or 14 pin
329 16 pin
45p 24 pin
26 pin
3-4OpF
1111,
20-250pF
100 -500pF
1250p1
13p
14p
36p
Sip
SILVER MICA
4.7, 6.8, 12, 18, 22, 33, SOLDERCON
PINS*
50, 82, 85, 100, 120, 150,
250pF 330pF
7p each 100 pins
DENCO COILS
Dual Purpose 'DP'
Rng. 1 -5 B,Y,R,W 69p
6-7 B,Y,R
1
-S
60p
74p
Green
Transistor Tuning coils
'T' Type
Rng. 1 -5 B,Y,R,W
RFC S choke
IFT 13/14/15/16/17
FT18/465 or 1.8m
78p
76p
70p
I
SOp
TOC 1
MW SF.R.
MW /LW 5FR
75p
72p
94p
EARPHONES
Magnetic
2.5mm plug
3.5mm plug
Crystal
3.6mm plug
SPEAKERS
80.3W
21"; 211"; 3"
2 }-
Iktr
OSP
ALUM. BOXES
with 11d
2 }x5 1x10" 469
472 1 x
4x5 x1 }"
4x2 }x2^
48p
46p
559
469
3x2x1"
624x2"
40p
709
7:5x23"
549
424x1
i"
8:6x3'
PEN
30p
Ssp
60p
166p
122p
1027x3"
10.1 0x3" 1í0p
12:5x3" 120p
1228x3" 180p
DALO ETCH
1Sp
1Sp
AF185
AF186
AF239
ASY28
ASY28
ASY50
RESIST
only 769
COPPER CLAD SRBP
LAMINATE
Single Sided 8 }x9)" dip
Double Sided 41x7" 35p
FIBREGLASS BOARD.
Single Sided 6x6"
64p
SIngle Sided 12x6" 11Sp
FERRIC CHLORIDE
11b Bag. 6Sp+ 30p (p 8 p)
8C172
BC117
BC147
7
8D138
lip
4511
RHYTHM GENE
R
TOR
this PW (May d, June
'76) Easy build Low cost
'7
Build
B
Rhythm
R
Generator. We are
the sole suppliers of the
th
complete Kit including the
CO
C
Case,
predrllled
printed
front Panel and the three
fr
Fibre-glass P.C. Boards.
Fi
Pr
Price
including VAT
Complete
C
Kit £41 85
(9.áp. and incur, £1 00)
Ready Built £48 85 (availR
able in limited quantity)
P&P
P
1
00
$
Send
SAE for complete list.
(Demonstration on at our
(D
retail shop)
r8
015
(copper clad)
2}
x
30"
2 }} x 5"
3
x
x
35"
x
17"
30
5"
20 x 17"
3
45 x 17"
329
35p
35p
40p
1059
145p
1859
okt of 36 pins
Spot faca cutter
Pin insertion tool
24p
3Sp
,35p
419
73p
115p
-
7iÁ055
7407
7408
7410
7410
7412
7413
7414
7416
7417
7420
7423
7425
7428
7427
7428
7430
7433
7437
7438
7440
7441
VEROBOARD Pitch
0'1
1Sp
74404
0.15
(plain)
1$p
20p
-
29p
60p
75p
110p
229
52P
72p
7443
7443
7444
7445
7448
7447
18p
UP
35p
38p
1Sp
1Sp
13p
20p
3Sp
SOp
3Sp
35p
1Sp
27p
22p
27p
27p
27p
3Sp
1Sp
25p
36p
27p
27P
15p
6Sp
6Sp
7481
7482
7483
7484
7485
7486
7489
7400
489
39p
74111
74116
74118
74119
74120
74121
74123
70p
15p
7451
1Sp
74141
7453
159
15p
74142
74143
74144
74145
74147
iSp
30p
26p
30p
BF177
BF178
BF179
BF180
130181
BF184
BF185
BF194
BF195
8F198
BF197
14
16
30
40
30
23
29
18
18
18
BF256
BF257
BF258
BOp
639
72p
i35p
409
409
33p
54p
439
539
1709
100p
100p
939
309
4Sp
639
54p
18
18
16
17
17
26
37
18
24
0070
0071
0074
OC76
D
ZTX301
ZTX302
ZTX303
ZTX304
ZTX311
ZTX341
0C139
OC140
0C141
OC170
0C171
OC201
OC202
TIC44
TIP29
TIP29A
TIP29C
TIP30
TIP30A
TIP3OB
TIP30C
MJE305565
MPF102
MPF103
MPF104
MPF105
30
30
30
30
MPSA06 30
MPSAS6 30
MPSA70 32
OC23 144
0C25 48
OC26 46
T1P35
2N698'
2N706
2N708
2N918
2N920
2N030
2143708
2N3709
2N3710
2143711
40
2N3772
S1
2N3773°
18
18
15
20
17
20
24
28
28
28
35
2141131
2N1132
2N1301
2141302
2N1303
2141304°
2N1305
2N1306
2N1307°
2N1308
2N1893
2143819
2N3820
2N3823
2N3888
2N3883
2N3904
2N3905
2N3908
2N4037
2N4058
SO
2141990
2N4061
2142217°
2N4871
45
55
23
2N2218A 20
2N4062
2N2160
2N4822
2N5457
2N5458
2N5458
2N5027
2N6027.
2N2219A22
2N2220A1i
167
259
TIP2955
2N3615°
2N3702
2N3703
2N3704
2N3705
2N3706
2N3707
28
18
13
30
12
15
2N897
2N2221
A21
2N2222 20
2N2303 30
2N2369 14
TIP36A370
TIP41A
TIP41B
TIP42A
TIP42B
2N3053
2N3054
2N3055
2N3814
47
ZTX531
ZTX550
TIP34A11S
TIP34B
2N29260
2N2926R
2N2926Y
2N3011
24
10
19
16
13
18
14
ZTX500
TIP31 S4
TIP31A' 5t
TIP31B 70
TIP31C 54
TIP32 64
TIP32A 68
TIP32B SO
TIP32C 99
TIP33 95
TIP33B112
TIP33C130
TIP34 110
2N2907A
2N2926G
IS
ZTX502
ZTX503
ZTX504
28
84
100
157
30
32
80
90
30
43
45
66
52
54
64
76
2N2906
2N2907
25
16
12
12
13
14
14
18
ZTX501
0083
MJE520 6S
MJE21155 9S
68
73
78
79
2N2483°
2N2484°
2N2646
6S
361141
40381
30
30
35
20
40362°
40130
2N2904
40673°
TI P3055* 60
OC28 SS
2N2904A21
ICL8038CC270p
SL403D
LINEAR IC'S
170p
LM300H
SL4 4A
709C 14 pin 29p
710
741C
747C
748C
AY-1-0212
AY-1-5051
AY-5-1224°
AY-1-87218
439
20p
70p
2Sp
5509
120p
349p
72p
1459
90p
CA3090AQ
2SOp
CA3123E
tor155
74148
74150
74151
74153
74154
74155
74156
74157
74159
74160
74154
74165
74186
74167
74170
74172
74173
74174
74175
74176
74177
74178
74179
74180
74181
359
LM380
gOp
MFC6040
MK50253
NE555
NE558DB
NE581
NE562B
S9p
2109
150p
1509
130p
NE566A
NE567V
140p
+ mx á AA119
S0p
196p
1019
1019
101p
101p
132p
132p
140p
315p
2159
5409
1539
11Sp
92p
103p
101p
1429
142p
106p
3019
Sdp
74191
70p
70p
63p
266p
74192
74193
74194
74195
74198
74197
74108
74199
1609
125p
125p
9SOP
494p
12Sp
79p
103p
1039
210p
210p
11
21
TBA810S
TBA920Q
TDA2020
TCA270SQ
5V 1A(703)
12V 1 A(T03)
18V 1A(T03 )
MVR12(T03)
TBA825B
1SOp
200p
Sp
Sp
10p
44p
439
Op
10p
6p
6p
0A90
0A91
OA95
0A200
0A202
PL4001
PL4004
PL4006
N914
N1001/2
N4003
N4004/5
N4006/7
N4148
Bp
9p
6
6p
tp
12p
S921
1A50V
1A100V
1A200V
1A400V
20p
24p
26p
27p
1ASOOV
29p
30p
lip
2A50V
2A100V
2A200V
2A400V
2A600V
4A100V
4A400V
4A800V
Sdp
539
110p
90P
649
SA100V
6A400V
SOP
BY122
BY164
54p
549
ZENERS
Rng:3-3V-33V
9p
17p
400mW
1.3W
Sp
Sp
Sp
VARICAPS
Sp
7p
7p
5920
(plasticl case)
4p
7p
MVAMI 270p
MVAM2 105p
SMOKE.
DETECTOR
TGS209
I
I
3!
31
31
i
723C(T05)
OA70
OA79
OA85
21
723C DIL
BRIDGE
OA81
11
REGULATOR
OA10
0A47
1
ZN414
F
RECTIERS
0A5
0A9
11
81478115
11p
10p
10p
12p
12p
39p
9p
40p
170p AA120
113p BA100
69p BY128
709 BY127
70p
70p
148p
$609
1609
iSOp
70p
559
46p
569
550p
459
99p
325p
270p
11
SN72702
SN76033
TAA550B
TAD100
TBA5400
TBA800
750P
MC1303L
MC1304P
MC131oP
MC1312PQ
MC1458P
MC1710CG
MFC40008
DIODES
1S0p
1609
65p
M252AA
17Sp
CA3018
CA3020
CA3028
CA3046
CA3048
CA3075
CA3081
CA3089E
LM301AM
LM381
LM3900
AY-5-3500. 610p
AY-5-3507° 111op
AY-5-4007 735p
83p
160p
160p
271p
O/p
233p
IS
0C45
30
30
30
BFX85 25
BFX86 24
BFX88 22
BFY50 13
BFY51 15
BFY52 15
BSX20 20
BSY95A 14
MJI91
150
MJE370 68
74182
74184
74185
74186
74188
74190
274P
SS
OC44
MJE371 i0
45
S4
0C42
0081
0081
TIS43
TIS44
ZTX107
ZTX108
ZTX109
ZTX300
SS
OC41
BFR40
BFR79
BFR80
125p
35p 74161
2759 74162
40p 74163
7492
7493
7404
7405
7408
74100
74104
74105
74107
74109
74110
7448
7450
7460
7470
7472
33p
32p
32p
32p
44p
99p
7Sp
WP
BOp
74128
74128
74132
7454
5Óq
7491
1059 74125
80P
13
A E191 p
Less
7473
7474
7475
7476
7480
120p
1059 74122
SSP
11
4518AE700p
4520AE 99p
DIGITAL ICs
7402
12
22
28
12
13
4028AE 74p
4029AE 94p
4030AE 45p
4033AE111p
4034AE131p
4040AE S8p
4042AE 67p
4043AE 111p
4044AE 7Sp
4045AE111 p
4046AE10Op
4047AE 74p
4049AE 44p
4050AE 44p
4055AE1o6p
4058AE1osp
4069AE 16p
4070AE 16p
1510AE124p
4000AE 16p
4001AE
4002AE 16p
4006AE 77p
4007AE tip
4009AE 6Sp
4010AE 44p
4011AE 16p
4012AE 16p
4013AE 44p
4015AE 81p
4016AE 44p
4017AE 71p
4018AE 71p
4019AE 44p
4020AE 90p
4021AE Sip
4022AE 78p
4023AE 16p
4024AE 549
4025AE 17p
1026AE1369
7401
11
11
BCY70
BCY71 IS
BCY72 1/
BD115 52
BD121 115
BD123 95
BD124 75
BD131 40
BD132 40
Mtch. pr.SS
BD135 SS
BD136 SO
BD137 45
9
1314139
BF115
BF244
BCY42
BCY43
BCY58
BCY59
12
12
20
BF595
75
65
22
26
21
33
33
33
32
30
10
10
14
15
12
17
32
32
35
16
BDY61
12
10
OC29
OC35
OC38
SS
BDY80
BF224A
BC441
BC461
BC462
9
9
SO
BD145
11
BC214L
12
12
13p
13p
14p
11
11
11
45
BD14o
BC182
BC182L
BC183
BC183L
BC184
BC184L
BC186
13C214
CMOS#
7400
9
20
10
12
13
12
12
12
BD139
16
16
20
BC212
BC212L
BC213
BC213L
40
17
BC108
BC108B
BC108C
BC109
BC109B
BC109C
P7
BC177
BC178
BC179
BC187
31
TTL 74*
DIL
TRIMMERS
AF181
Bc107
POTENTIOMETERS (AB or EGEN)
Carbon Track, 0.25W Log S 0.5W
TANTALUM BEAD CAPACITORS
0.1 -385pF
00 2 3850F
SOV: 2000, 72P;
BC171
49
59
55
48
60
43
34
API 80
ELECTROLYTIC CAPACITORS: Axial lead type (Values are In EF).
250V: 1000F, 40p; 100V: 20, 6p; 63V: 0.47, .0, -5, 2.2, 2.5, 3.3, 4.7, 6.8,
1
ACY22
ACY39
AF178
AF179
400V: 0 001, 00012, 0 0015, 00018, 0 p¡10p22, 00033 Sp; 00047, 0 0068, 0 01, 0 015,
0022 Sp; 0033, 0047, 0.068 8p; 0.1, 0.15, 0.22, 10p; 0.33. 0.47, 11111.
160V: 0.1, 0.154p; 0.22 Sp; 0.33 6p; 0.47 10p; 0.68159;1 0 18p;1 .5 26p; 2.2 24p; 47211p
DUBILIER: 1000V: 0.01, 14p; 0022, 15p; 0047, 16p; 0 1, 19p; 0.47 439.
l-5249; 2.2 2Sp.
ACY21
FEED THROUGH
V AT
0.22, 0.33 9p; 0-47 10p; 0.68 14p; 1.0 19p;
ACY17
ACY18
ACY19
ACY20
AD140
AD149
AD161
AD162 35
Mtch.pr.90
AF114 ts
AF115 18
AF118 18
AF117 18
AF121 33
AF121 30
AF125 30
AF128 30
AF127 30
AF139 33
Applicable to U.K. Customers only. All prices are exclusive of
VAT. Please add 5% to devices marked To the rest add 25 %.
Callers welcome to our retail shop at 33, Cardiff Road, behind Watford Football Ground. Monday to Saturday. Ample Free Car Parking space available.
POLYESTER CAPACITORS: Axial lead type. (Values are In uf).
POLYESTER RADIAL LEAD P.C. TYPE (Velues are In uf).
250V: 0.01, 0015, 0.022 Sp; 0033, 0047, 0088, 0.1 6p; 0.15 7p;
AC187
AC188
BC148
BC149
BC1S4
BC157
BC158
BC159
BC167
BC168
BC169C
BC170
28
14
14
14
24
25
14
14
15
35
21
25
24
29
16
78
48
48
35
200p
1
1
1:
11
I
SCR's*
Thyrlston
A50V
1A100V
1A200V
1A400V
A600V
3AS0V
3A100V
3A200V
3A400V
3A600V
5A400V
7A400V
Cl 06D
1
1
1
MCR101
TIC44
2144144
1
TRIACS
3A400V
6A400V
6A500V
10A50oV
1
1
1
1
40430
40669
DIAC
ST2
OPTO ELECTRONICS.
LEDs with clips
TIL209
14p
0.2" Red
ISp
Larger Yellow
Green, Amber
OCP 70
2Op
OCP
ORP 12
ORP 61
Sip
71
2N 5777
40p
6Sp
Sop
DL704 .3" Red
DL 707 .3" Red
DL727 .5" Red 1
DL728 5" Red 1
DL747 .6" Red I
XAN354 .3" Grn 1
XAN852 .6" Grn 1
MAN 3610
MAN 3640
MINITRON 3015F
36p
Practical Wireless, May 1976
1
1
(Continued from other side)
WATFORD ELECTRONICS
:HOKE
FOOT
vliniature
o0m', 7Jp
£2.80
Connectors
SWITCH
JACK PLUGS
Snap on PP3 6p
Snap on PP9 91, Screened
chrome
2 5mm
10p
3.5mm
14p
Std. MONO
19p
Std. STEREO
32p
+Pedal
NOBS. fits }" shaft
th grub screw, except
(push fit) 6 K8 (for
ders).
Black or White pointer type
!Slim silvered aluminium
Black 1 1" with chrome rim
Black serrated. Metal top with
line indicator 33mm diam.
Black fluted metal top and skirt
calibrated 0-10. 37mm diam.
PK2 as K5, pointer on skirt
Black, knurled, tapered. Metal
top & skirt. Calib. 0-10, 30min
Black or silvered for slider pot
2
89
o
15p
assorted colours
Metal screened
BANANA
(1760)
0-18V
1A
0-15 1A
V 1A
2 0-12 500mA
0-12
195p(20)
285p (48)
340p (62)
230p )20p)
196p (48)
1A
330P (48)
237p (48)
185p (48)
110p
54p
54p
42p
Pulse Transformer :1
Mini Orly. Pri 20K Sec 1K
Mini O/P Pri 1.2K Sec 3.20
IT Mlni O/P Pri 1.2K Sec 80
6 P) shown is to be added to normal
stal charges
r
1
44
700
Plugs
Sockets
12p
8p
10p
8p
7p
4mm
2mm
ICS can provide the technical know ledge that is so essential
to your success, knowledge that will enable you to take advantage of the many opportunities open to the trained person. You
,tudy in your own home, in your own time and at your own
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coaching until you are successful.
17p
22p
1Sp
& Guilds Certificates:
Telecommunications Technicians
Radio, TV, Electronics Technicians
Technical Communications
Radio Servicing Theory
Radio Amateurs
Electrical Installation Work
MPT Radio Communications Certificate
Diploma Courses:
Colour TV Servicing
Electronic Engineering and Maintenance
Computer Engineering and Programming
Radio, TV, Audio Engineering and Servicing
Electrical Engineering, Installation
and Contractin
City
5p (Single)
7p (Double)
12p
fop (Triple)
6p
7p
7p
7p
Blue, Green, Yellow, White
14p
LES BULBS 6v and 12v
7p
MES HOLDERS Chrome cover, Red or
Amber, Jewelled top
50p
MES BULBS 3.5V 6V 12V
7p
NEONS Mains, Sealed with Resistor.
Sq. Top, Red or Gm. Round Top Red 21p
Neon with leads, 95V AC (No resistor) 9p
SWITCHES'
SLIDE 250V:
TOGGLE: 2A, 250V 1A DP
10p
SPST20p
1A DP C/O
12p
DPDT 24p
lA DP
9P
SUB -MIN TOGGLE
90p
1A
break
contacts
LAMP HOLDERS ANO LAMPS'
LES HOLDER Dorne shaped, Red,
90p
90p
0-22 500mA
0- 15100mA
24-20.15 -12 -0 (MT7OAT)
24- 20- 15 -12 -0 2A
Moulded
with
/p
6 240 °)
22p
8p
mary 220 -240V
2
13p
lip
22p
22p
32 x 70mm
(Miniature) 100mA
-9 (Miniature) 100mA
0.12 (Miniature) 100mA
10p
13p
PHONO
0-1mA, 0 -500uA
Price £414
-8
Open
metal
8p
CO-AXIAL (TV)
20p
tANSFORMERS MAINS
body
8p
pin Loudspeaker
3, 4, 5 (180°
4NEL METERS. Full scale
a 46 x 35mm req. 1.1." hole
iOuA
0.100mA
50aA- 0-50aA
100uA
0-500mA
100aA-0-100uA
0-1 Arnp
5000A
500uA-0-500pA
mA
0-50V DC
£3.05 each
imA
0-300V DC
EDGEWISE
OmA
"S"
iOmA
"VU"
ce £2.85 each.
Plastic
DIN
9p
10p
TECHNICAL TRAINING IN
ELECTRONICS TELEVISION
AND RADIO SERVICING
SOCKETS
SP changeover
SPST on /oft
DPDT 6 tag
45p
400
64p
DPDT Centre off lap
PUSH BUTTON
Spring loaded
SPST on /oft
SPDT C /over
DPDT 6 Tag
SWITCHES PUSH BUTTON:
Push on /Push off, spring loaded
Miniature Non Locking
Push to Make
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a
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ICS To:
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SW84UJ.
a.J,.i.i...;.
;
Push to Break
15p
25p
= ..,il.. ...,i.. ....
SP changeover centre off
ROCKER: (black) on /oft 10A 250V
25p
20p
IM
46p
1p /12w, 2p /6w, 2p /2w, 2p /4w,
3o/3w, 3P /4w, 4p /2w, 4p /3w
26p
I
ROCKER (white): 10A 250V
ROCKER: Illuminated (white)
.._
..
lights when on. 3A 240V
ROTARY:
.,.
.,
INI00
............
INDEX TO ADVERT' SERS
Flairline Supplies
Alben Engineering
G.T. Technical Information Service
...
90
"'
...
...
Ambit International
ASP Ltd. ...
A.S.P. Ltd. ...
Audio-Optics
A.H. Supplies
...
...
...
...
...
...
...
...
...
.
...
..
...
...
...
Bamber, B....
...
...
Barclay Electronics...
...
Barrie Electronics
Bentley Acoustic Corp. Ltd.
B.H. Component Factors Ltd.
Bi -Pak Ltd....
...
...
Bi- Pre-Pak Ltd.
...
...
Birkect. . ...
...
...
Boffin Projects
...
...
...
...
...
...
............
...
...
...
...
...
1
...
...
10,
...
...
.,
16
40
75
68
89
22
81
83
6
8
72
II
19
81
91
British Institute of Engineering Tech18,
gY
British National Radio
School
...
...
J. Bull (Electrical) Ltd.
Bywood Electronics
&
64, 82
Electronics
...
6, 67
...
...
..
85
...
...
...
84
C.D.I. Ltd. ...
...
...
...
... 36
Cambridge Kits
...
...
...
... 91
Cambridge Technical Developments Ltd. 92
Caranna C ....
...
...
...
... 90
Chromasonic Electronics ...
... Cover iii
C.J.L. Ltd . ...
...
...
...
... 76
.,. 89
Cleveland Supplies
...
Codar Radio Co. ...
"'
...
... 96
uEp
ieson...
Copper
Ltd.
...
... 91
Copper Supplies ...
...
...
... 71
Crescent Radio Ltd.
..
... 75
'
"'
Crofton Electronics
e
...
...
... 93
91
Crowborough Electronics
D.E.W. Ltd.
Doram
Eaton Audio
...
...
...
...
Electronics Design Associates
Electronic Mail Order Ltd.
Electronic Supplies (Print -a -Kit)
Electro -Tech Components
Electrospares
...
...
Electrovalue Ltd. ...
...
Practical Wireless, May 1976
...
...
...
.
..
...
...
...
...
...
...
...
...
...
...
...
92
35
84
82
76
18
36
92
16
.....,i
...
61
Radio Component Specialists
Radio Book Service
...
Radio Exchange Ltd.
...
Ramar Construction Services
Radio SocietyY of G.B.
...
"'
89
R.S.T. Valve Mail Order Co.
Radio & T.V. Components Ltd.
...
...
...
...
...
Harverson Surplus
...
...
Helme Audio
...
...
Henry's (Radio) Ltd.
...
...
Home Radio Components Ltd. ...
...
...
...
...
...
93
...
21
I.L.P. Electronics Ltd.
...
9
arfields
"'
"'
Gold ring Ltd.
...
Greenwald Electronic
Greenwald Electronics
Grimsb y Electronics
"'
...
...
...
"'
"'
H.A.C. Short -Wave Supplies
H.M. Electronics ...
...
Integrex Ltd.
Intertext I.C.S.
...
...
...
...
...
...
...
...
Kensington Supplies
Kinnie Components
Com
...
...
...
Lasky's Radio
Lewis Radio...
Linear Products
Lynx Electronics
...
...
...
...
...
...
...
...
...
...
...
...
M.C.L.
...
...
...
Manor Supplies
...
...
Magnetic Components Ltd.
Magnum Publications
Maplin Electronic Supplies
Marco Trading
...
Marshall, A. & Sons
...
Mawson Associates
...
Milward, G. F.
...
...
Minikits Electronics
...
...
...
..
Newmart Electronics
...
Orchard Electronics
...
Partridge Electronics Ltd.
...
...
...
Precision Petite
...
...
P.B. Electronics
Pulse Electronics
...
...
...
...
91
91
17
91
22
68
95, 90
...
...
...
...
...
...
.
Salopp Electronics ...
Saxon Entertainments Ltd.
Scientific Wire Company, The
Simtech Engineering Ltd.
Sinclair Radionics Ltd.
Sintel
...
...
Southern Valve Co.
...
Sur p lectronics
...
Swanley Electronics
...
...
Tape Talk
..
...
.
...
...
...
...
...
...
Stereo Cassette Lending Library...
...
...
...
...
...
...
...
80
92
23
91
20
...
39
14, IS
..
87
...
...
91
.
7
91
...
90
52,
...
...
...
...
53
76
18
90
..
72
87
...
-..
...
86
40
16
89
...
81
...
70
92
...
...
90
92
T.V. Technical Publications
Technomatic Ltd. ...
...
Teleradio Electronics
Time Micro Electronics ...
Trampus Electronics
...
Tuac Ltd. ...
...
...
...
...
Vero Electronics ...
...
...
...
Watford Electronics
...
...
...
...
...
...
...
...
...
...
...
...
...
63
...
84
...
96
.....
...
...
91, 92
...
71
Cover ii
... 4,
5
87
Cover iv
...
...
...
...
...
12
89
63
91
...
20
...
...
6
...
...
93
...
...
8
...
86
...
Riversdale
...
...
...
...
90
2, 12
... 64
... 63
.........
."'
...
.
84
Web Europa
...
Wentworth Radio
...
West London Direct Supplies
Michael Williams Electronics
Wilmslow Audio ...
...
...
Wrights, S. G.
Xeroza Radio
...
"'
Aero Services
...
77
Z. &
I.
...
94, 95
36
89
93
72
95
Head Office and Warehouse
W2
LONDON
&
Z
44A WESTOOURNE GROVE
SSF
AERO SERVICES LTD
I
85 TOTTENHAM COURT ROAD
LONDON
RT ROAD
Tel: 580 8403
Open all day Saturday
Please send all correspondence and Mail- Orders to Head Office
Tel: 727 56411213
MULTIMETERS -MADE IN USSR
AC/DC
MULTIMETER
TYPE U4315
AC /DC
MULTIMETER
'
TYPE U4324
ranges covering
D.C. current
604A to 3A;
AC current
33
-3A;
300MA
1200V
AC voltage:
ranges
covering:
2.5A; AC /DC
voltage: 1- 1000V;
m°
Resistance 30052500kû; Capacity up
to 05MF ;Transmission level: -15 to +2db;
Sensitivity: 20kûJV DC, 2kû /V AC.
3-
`
Resistance:
5000-500k1
PRICE
-10
D.C. current
50µA -2.5A; A.C.
current: 500MA-
-,
900V
Level:
TAA263-3 stage low level amplifier.
Bandwidth DC to 600kHz. Supply voltage
Output power 10mW 15052 load.
Typical gain 77dB. TO72 case.
£065
TAA293-Med. freq. amplifier up to
600kHz. Supply voltage 6V. Output
power 10mW into 1500. Typical gain
£0.65
89dB. TO74 case.
TAA320 -MOST stage followed by a
bi -polar transistor. Gate - to - source
voltage 9-14V. Drain current 1MA.
Power dissipation 200mW. TO18 case.
£0.60
6 -8V.
42
0.6-
DC voltage:
LINEAR I.C. AMPLIFIERS
to
Sensitivity:
+1
db vity:
iv ty: DC.
4,000 o.p.v. A.C.
Instrument is powered by re- chargeable
nickel cadmium batteries.
PRICE £10.85'
£11
HIGH GAIN DARLINGTON PAIRS
25'
TRANSISTORS FOR T.V.
APPLICATIONS
R2008B
R2010B
BÚ126
0-95
1.65
Plastic 3-lead case encapsulated DAR LINGTON pair. Typical current gain
30,000. Max. collector voltage VOS° 40V.
Max. collector current 400mA. ICBO =
10nA. BC516 -PNP £080. BC517 -NPN
£0.80
1.55
2.00
BU133
BU208
55
1
Full description of the above, as well as other instruments, is available in our Illustrated 126 -page catalogue, which also includes
price list of comprehensive range of transmitting and receiving valves, semiconductors and passive components. Please send 20p
for your copy.
HANDLING AND POSTAGE CHARGES. When ordering through our Mail Order Service please add
£1 00
for each instrument
and 20p in £ for other items (subject to a minimum charge of 20p).
VALUE ADDED TAX: Prices are exclusive of VAT. Items marked with asterisk are at present rated at 8% and others at
25 %.
This percentage must be added to the total value of the order including handling charges.
GY501
0232
VALVES
A1065 1-25 ECL80 0.60
0100 ECL82 0.40
ARS
ARP3 0.60 ECL83 0-75
ATP4 0.50 ECL86 0.60
0-6S
B12H 3.00 EF38
DAF96 0.60 EF37A 110
0.70
DF96 0.60 EF40
0.75
0106 0.75 EF41
0.35
DL92 0.50 EF80
1.25
DL96 0.70 EF83
0-40
EF85
DY86187
0.45
0.45 EF86
0.35
DY802 0.45 EF89
0.60
EF91
E88CC/01
0.50
1.30 EF92
EF95
0.45
E180CC
1
00 EF183 0-40
0.40
EF184
E182CC
3.00 EFL200 0-75
0-70
EA50 0.40 EL3/
0.70
EL35
EABC80
2.20
0.40 EL37
0-60
EAF42 0.70 EL41
0.30 EL81
0-60
EB91
O.35
E8C33 1-00 EL84
0-60
EBC41 0.75 EL85
0.50
EBF80 0.40 EL86
0.50
EBF83 0.45 ELOO
1 00
EBF89 0.40 EL91
0.40 EL95
0.70
EC52
ECC81 0.45 EL504 0.80
ECC82 0.35 EL821 1.80
0.70
ECC83 0.35 EM31
ECC84 0.35 EM80 0.55
ECC85 0.45 EMU 0.40
ECC86 1.25 EM87 1-00
0-45
ECC88 0-55 EY51
EY81
0.45
ECC189
0.60 EY86/87
0.45
ECF80 0.4S
0.50
ECF82 0.45 EY88
ECF8010.75 EZ40 0 70
0.75
ECF8042.50 EZ41
ECH42 0.6S EZ80 0.30
0.35
ECH81 0.40 EZ81
ECH84 0.60 GT1C 5.00
GZ34
GZ37
KT86
KT88
MH4
ML6
0A2
0.00
0.65
0.00
1-00
2.90
3.15
1-00
0'75
0.45
0.45
PABC80
0-40
PC86 0.65
PC88 0.05
PC97 0.55
PC900 0.55
PCC84 0.45
PCC89 0.60
PCC789
0.65
0132
0.50
PY82 0.45
PY83 0.50
PY88
0 S0
PY500 1.10
0.55
QQV03-10
PY801
1S0
QQ V0640A 8.00
QV03-12
1.60
SC1/400
W
PCF80040 SCi/600
PCF82 0 40
PCF84 0.05
PCF88 0-6S
PC F200
0.90
PCF201
0. 00
PC F801
O
SS
PCF802
p SS
PCF805
PC F806
1-10
0'00
PCH200
0.00
PCL81
PCL82
PCL83
PCL84
PCL86
0.60
0-40
0.70
0-S0
0.60
PCL805/85
0.60
PFL200 0-70
PL36
0.60
PL81
0.55
PL82
0.50
0.50
PL83
PL84
PL504
0-50
0.65
e valves are imported and
prices vary for each delivery, so we
reserve the right to change prices
for new stock when unavoidable.
A lot of the
PL508 0-OS
PL509 1 36
PL802 1.05
PY33 0 35
PY80 0.00
PY/81/800
SP61
5.50
0 00
6 00
1721
0.50
1.00 ÚL84
0.10 ÚY41
0.50
0S0
1 00 UY85
0.75 VRl05 /30
U191
0.45
0.00
0801
VR150 /30
UABC80
0.45
0.45
UAF42 0.70 X61M 1 S0
0.75
UBC41 0-00 X66
UBF80 0.50 Z8000 3.00
UBF89 0.50 Z801U 3.00
1-00 Z900T 1.50
UBL1
0.55
UBL21 0-75 1A3
030
UCC85 050 IL4
0 50
UCF80 0.00 IRS
0 35
UCH42 0.00 1S4
0.35
UCH81 0.50 1S5
IT4
0.35
UCL82 0-45
0.75
UCL83 0-70 X28
0.50
0-70 2D21
UF41
S.00
UF80 0.40 21425
3A4
0.60
0.50
UF85
0.40
0.50 308
UF89
0.50
0.70 3S4
UL41
U25
U26
U27
I
TRANSISTORS
AF118
BAV70 A Fi 24
AF125
AC113
AC126
AF126
AF727
AC127
AF139
AC128
AAZ12-
AC176
ACY17
ACY18
ACY19
ACY20
ACY39
ACY40
AD149
AD161
A0182
ADZ11
ADZi2
AF114
AF715
AF116
AF117
A F178
AF188
AF239
AFZ12
ASY26
ASY27
ASY28
BC107
8C108
BC109
BC113
BC118
BC118
BC136
BC137
BC148A
BC172
0.05 BAM6 0.60
3V4
6AN8 0.70
581251M
500 6AQ5 O-55
58/255M
6A05W
5.00
0.70
5B/258M
BASO 0.50
5.50 13AS7G 1.00
5RIGY 1.00 6AT6 0.60
5U4G 0SS BAUE 0.40
5V4G 0.115 6AV6 0.50
5Y3GT 0-60 6AX4GT
5Z3
OC6
6CBB
BCH6
6C L6
806
SEAS
8F7
6F8G
6F12
6F17
0.75 8F33
1.20
5Z4G
0-00 6AX5GT
1.00
BAB7 0.60 687
0.70
6AC7 0.60 6BA6 0.40
6AH8 0.70 613E6 0.40
OAKS 0.45 6BG6G 1.00
6A K8 040 68J6 0.75
6AL5 0 30 BBO7A 0.00
6BR7 1.30
6AL5W
SZIGT 0.65
6AM5
6C4
OHO
0.40 6K8GT 0.55 7Y4
1110 9D2
0-S0 6LBM
0.50 BL7G 040 906
1.80 OS A7 0.55 11E2
0.75 6SC7 0-75 12A8
0-45 6SG7 05S 12AT6
0.75 65.17 0 60 12AT7
12AU7
1.10 6SJ7GT
0.75
0.35 12AX7
0.60 65K7 0.60 12BA6
126E6
1.00 6SL7GT
0S5 128H7
3.50
12C8
0-45 BSN7GT
BJ4WA
O
SS
1-2S 6S07 0.60
0.65 BV6GT 6 N
0.45
6J5GT 0.55 6X4
6.18
0.35 6X50 0 40
6J5
6J7
6J7G
0'BS BX5GT 0.55
BYBG 0 05
0.40
6KBGT 0'80
0.55
0 60 6BW8 1 10 6K7
1 .00
88W7 1.00 61(7G 0.35
0 6S
BZ4
6-301.2
0.00
0.60
787
Please write or phone for current price of any
of the translators, diodes shown below.
2N4058
0C206
OC29
CRS3140
8C172A
BC212A
BCY31
8CY33
BCY72
BF115
8F187
BF173
CR5251025
0E7115
0E7116
0EX88
NKT222
NKT304
NKT404
0C35
0C38
0C42
0C44
0C45
0A5
0A47
BFY51
BFY52
BSY27
A7
0
0073
0075
0078
0078D
0A71
0A73
0A79
0 A91
0081
0082
8SY38
BSY05A
BY100
BYZ18
CRS1/20
CRS1/30
CRS3/10
CRS3/20
CRS3/30
0A200
0A202
OAZ200
0C22
0C25
0C26
0C28
0C82DM
0083
0083B
0C139
0C140
0C170
0C172
0C200
0C204
2N4061
ZR22
2N52O5
2N456A
3N126
3N128
3N154
3N159
SX754
25303
T12082
40235
40250
2N525
2N806
2N708
2N918
2N1305
2N1307
2N1300
2N2082
OC70
13F185
ZR11
ZR21
2N4172
2N2411
2142989
40251
2N3053
2N3054
2N3055
2N3391
2N3730
2N3819
2N4038
N25
N23A
N38A
N43
N70
N677
N4148
N4785
MINIMUM POSTAL ORDER £1. PERSONAL CALLERS WELCOME.
MANY OTHERS IN STOCK inc /ud
UK Postage E1E2 20p 52-53 30
VIDECON
TUBE
Typa P8048
English Else.
E20
Cathode Ra Tubes and Special Vale. s. U.K.
E3 -£5 40p. Over £5 free. C.O.D. 50p extra.
TEST EQUIPMENT
CO 0MO
0.60
0.50
6.00
0.60
0.45
0.45
0.35
0.35
0.50
0.55
0.55
0.60
3.75
DM,
THE VALVE WITH A
GUARANTEE
0.70
9003
0-40
0.60 9004
35W4 0.55 9006
0.40
121(5
1.50 35Z4GT 0.70
121(7GT
C.R.
500 0.45 TUBES
O SS
50C DOG
12KBGT
1.20 DG7-5
0.75
100
75
1200
12Q7GT
75C1
075 0G7-32
0.50 76
0.75
15.00
12SA7GT
78
0.70
DG13-2
0.80
0.75
1600
12SG7 0.55 80
85A2 0.75 MW13-35
12SJ7 0.55 803
300
35 00
12Y4
040 805
1600 VCR139A
1.00 807
14S7
0-75
0.00
19AQ5 0-70 813
6.50 5FP7
8.00
1903 8.00 866A 1.60 88J
11.00
6.50 931A 6.00 B8L
19G8
9.00
19H5 15.00 954
0.50
20P3 0.60 955
0.50
1.10 956
20P4
0.50 SPECIAL
25L8GT
0.50 VALVES
957
0.70 1629
0.70 CV2339
30C15 1.00 2051
1.00
4510
30C17 1-10 5933
3.00 M503-22J42
30C18 1-10 6057
0.60
6000
1.00 6060
3oFS
0.70 K301
7.00
0.60 KRN2A
3oFL1 110 6064
1.00
6.00
30FL12 1.10 6085
0.80 725A 25.00
1.00 6067
301-15
2.50 TY4 -500
30L17 1.00 6080
3.35
.00
30P12 1.00 8146
30P19 1 00 61468 4 00 2J/19230
5.00
14000
30P Li 1-00 8020
0.40 2.1;52A
30PL13 1.10 9001
0.55
7500
30PL14 1.10 9002
12E1
35L6GT
VALVES AND TRANSISTORS
valves,
Telephone enquiries for
transistors, etc., retail 749 3934;
trade and export 743 0899.
COLOMOR (ELECTRONICS) LTD
170 GOLDHAWK RD., LONDON W12
LARGE SELECTION
PLUBICON TUBES
Type XO 1071 Mollard
0.60
E150
Open 9-12.30, 1.30 -5.30 p.m.
Closed Saturdays.
London EC4A 4AD. Printed in England by Index Printers,
Published on approximately the 7th of each month by ii'C Magazines Limited. Pleetwsy Douse. Yerringdoa Street,
News Agency Ltd. PavcnlOAL Wtaatwaa is sold subject
Dunstable, lieds. Sole Agents for Australis and New Zealand-Cordon and Ootch (Asia) Ltd.; South Africa-Central
be lent, resold. hired out or otherwise disposed of by way of Trade st
having
been
given,
trat
of
the
Publishers
the
written
consent
without
not,
namely
that
It
shall
the
conditions,
to
following
that
it shall not he lent, resold, hired out or otherwise disposed
and
to
V.A.T.,
le
subject
price
the
selling
where
excluding
Eire
more than the recommended selling price shown on the cover,
literary or pictorial matter whatsoever.
of in mutilated condition or in say unauthorised cover by way of Trade or Willed to or as part of any publication or advertising,
JL
IT Tpp
(
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C
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19p
£1
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59p
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£1.75
El .29
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CD4019AE
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El .64
E1.53
El .83
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í2.3l
98p
£1.28
íI.56'
01p
004089A8
004049Áf
0040508E
004051ÁE
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£7.15
EI. 59
004060ÁE
(040668E
0040680E
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99p
E1.44
6917
5817
4617
69p
58p
46p
£2.39
CI 9'9
289
7417
CD4069AE
281'
2417
004070ÁE
CD4071AE
CD4077 *E
28p
280
24p
240
59p
7117
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I9p
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1
automatic Poloriry de rpd q
Supplied with App do to and circa',-
slope integrating,
booklet.
fó.59.,
s.:
OUR PRICE ONLY
The
4Y.512241
1
tick /oek
Arorher marvel (ram G.I. A I6 P;^
I? -76 hr. Clock I.C. with 25 pin <apab ;l ;ry
and low external parts coat
Supplied w'14í
nufacHrers detailed leaflet ç3,950linc.
VÁ7) ,Leader alone 2017 'full 8;r
(excluding case, available towards
end of 1975. Phone Clive for de roils.
^u,
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F.M.
1171185
LP.1400
Multiplex
3p.
317'
0409
617.
317
7410
6p
°'3
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7417
7120
7427
7430
717
24p'
22:17
6p
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20p
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7p.
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22:p
18p
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75p
7442
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7447
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3217
4717
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74100
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la/ors 100 mA
'8105WC 190 -921
7811200 II0 -921
6017
78115WC 110 -921
6017
60p
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1-1311501 -411
8517
78M1290
01.35
78M15110
'8M181-1C
£1.35
78M24HC
El .35
CI
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1M707
?40C r70-.??0 El
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10030
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880339
El .99
IM773N
£0.99
LM377N
£2.71
£1
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}
1,9
02727
6017
Suitable
43p
Insouments, Cl.annel Indicators
Our 17-'198 44.75
each
't
Clocks. Meters,
for
Motorola ML ED 500
?Op
n a
Ip
2117
3117
,,6
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50p
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Free
0
S5p
4517
4617
3617
45p
670
4017
OB
y/.,'
lens
silo
1
1ML ED
10
100'
1
10'
27p
89p.
?4p
23p
Green
Orange
27p
290
27p
31p
290
33p
35p
2817
2317
Yellow
3417
3117
7517
32P
74121
dip'
2917
74 141
74145
'Bp'
£1.06'
71101
£3.20
4419?
74193
74196
01,35
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by
co Bnh
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61.64
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88 p
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14p
15p
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20 -0
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2d -0
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28 -0
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2/17
deduscr
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from others
9p.
IOO mA
100 mA
10I
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90p
90p
BOp
80p
8817
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£3.00
£3.75
(DAM°
08612111A
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SWITCH
1
to 9.
El .49 each
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all [1.82' each
all El.8 ? Each
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p/s/s/1
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100
Our Bulk Btying Power enables a
repeat of act Special O(le,
0,33u »L IT 7071 90p.'í ;nc. VAT
100'
10-
1217
1Op
I6p
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209
27p
30p
35p
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25p
25p '
3517
3317
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2917'
0.63
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OPTO/SOLATORS
ILI 4N23
6 pin
1.
or 171-7ló
industry srandord
5KV isolation
package
EI
.Op.
Serandaries
917
.14
El
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£2.43
MAINS TRANSFORMERS
6 -0
a -0
11.34
E1
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J
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LI
ít.25
digits, clock warm setting
0VM ;npor Scaling etc.
's
3Ip
68p
£1.02
£1.00
]4160
a
d,u. lens
clip. lens
111-2091
3417
74154
74174
01
774940
£2.'6
BCD encoded digial switch
Reading 0 to 9
Suitable for
7
0.2"
0.16"
35p'
SJp
v...4
7C4830S
10ÁI41?
1081415
í0A2010
£2.84
op-on plasr'1c retainer
s
74121
6317'
£5.24
í908o70
£4.71
IDq I405
£7.50
'
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24p
30p
30P
S5p
A2700
104760
LIGHT EMITTING' DIODES
07v
2Ip
E2
86p
£4.71
D1G 1741
v
15p'
2117
EI .24
í8A820
TIA9200
TB ,89900
Red, green, yellow, Otongel
Each
1Red Green, yellow»
all E2.3? Each
Red. Green, Yellow, Orange,
Fmcl
E4t,h
9nly,
XI î242t
Common Cathode ns Common 411748 ,Red 7117yí
NOTE- MAN 4000 Series pin ours ore 14 pin 4'11 the same os MAN 50, 70 and 80 series.
9092 package
pp
3917
El .11
El .24
TBA810AS
7001054
1007170
with devices IlOp 9lorrel
Tree
í8Á8105
TC
devices /101176118)
Leaflet
Series
0.33 lirroni. DL 407 5<r'1
0,33" Monsanto MAN 50'70'80/3600
0.33 x, ,ton XAN 70 Series
0.43, Monsanto MAN 4000 Series
0.63 l'nan ;. D7747 'Jumbo' Sr.- cos
Low cos, Red Ga AsP
6717
18,8800
£5.06
£2.96
£2.63
£1.87
£2.63
£1.22
£2.09
£2,75
SN75491N
SN75492N
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£5.06
£5.06
51-Á37D
$1-440
85
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£2.79
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1BA7500
£1.29
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19Á7p0
69p
N E563
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180707
L041820
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£1.25
NE565N
NE566V
NE567V
SD6000
CI.25
Ú,V82
El .03
EI .03
í8Á615C
£1.16
LM372N
LM381
i8Á6 ?58
N E546A
009371
1-80380
£5.29
IBA6?5A
£1.45
£2.85
£2.09
1.61370N
T8Á56000
£4.80
£9.99
(TO-3)
NE5401
92.34
£2.25
LM309k
E1.25
El .0?
£1,01
5917
NE556
NE560B
NE561 B
N E562B
75
£2.75
£5.03
T8Á5000
£1.45
NE555V
f2.4.3
£3,45
1885300
78A5400
1065580
MVR15V
57p
87
El .44
£2.59
£3.16
£3.85
£3.27
£3.7?
£5.29
P
(90 -991
918 pin dip)
£1
£2.16
I
£1.45
(TO-3)
67
pin dip, 59p
El .50
TAA310A
TAA320
7AÁ350
IBA ?OS
988231
TBA?81 I7 ?3,
2V
LM308 7 10 991
E1 .96
980
0M308 S (8 pin dip''
£7 .92
LM308A 1170-991
LM308A S 18 pin dip/E6.90
£2.09
£2,09
£2.09
£2.09
£2.09
78
M(TR
TAA ?63
TAA300
TAA370
1AÁ550
1AÁ520
IAA700
MVRSV
110 -991
6517
LM301S I8 pin dip 15917
SIB
92p
C6040
MM5314
MM5316
LA/13011
7190 -991
92p
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85p
2
SOP
6?
6517
B59
5017
2617
£1
129 `5m-3 o1
L130 SOT -321
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32p
45p
7?p
11.VÁ1
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2617'
32p'
26p
E2.92
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5.1.46
£I 46
Decimal Polnis
5717
2517'
0517
£1.46
LM30IA
0M301Á
18M0500
-31
/10.3.
003611 110.31
103771 T0-31
L00571
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34
ES
6817
MC1495L
84.48
£1.01
MC1496G
MC3302P £1,65
MC3401P
8117
MFC4000B
87p
MFC4060A
85p
MFC6030A
85p
LED DISPLAYS
L;oon., Double Digit Dispinys
W
NEW
0.5" Common Anode,
R'H
1
'Ip'
2517'
81.76
849
0Á3401E ilk/13900, 68p
CA3600F
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MC 1310, 2, 4 0 5
lop
7117
6217
6217
87
2517
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7N414 Leal
í8p
62p
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7492
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decoder
117
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7517'
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op
317'
85p
0491
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£8,60
£6.95
7y'
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I.F. Soip
Op
617'
0485
7486
tuner
,
LPI186
217
617
7482
80Ú1-1-ÁR0 MODULES
OP
50
'476
Still make the simplest, highly
reliable
217
7108
417
7474
0475
.
Op
2p
CA30898
CA3097E
CA3 23E
E1.86
01.86
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49p
F.M. sr.1.F
1805ÚC 170--20, E1.72
78121-8 /IO-217, El .7?
78151K /10-220' El .72
1818ÚC 110 -zpl E1 71
100`
7402
7403
7401
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(Dora and Circuit BOOklen done 700
25-99
I4p
lap
7400
This stare -of- the -art MOS LSI chip contains
all the logic necessary for a 3'. decade, dual
DVM
I
Regula'on IA
TTL
1_?4
Y
I.C.
C
--
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CA3062
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£1.60
MCI350
59p
CA3081
4617
082480170 -31
w2l, 1ea(le, .
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114
89p
MC339P
59p
5N'6660NfiBA1 p, ISP
SN'6666N CA30651 E 1,12
£1.46
MC1330
88P
C3080
83P
368
E1,04
42P
781780 )T0 -31
78151C' TO-3r
781880 rl. -31
E2.76. Comple
Type 101 RED
R
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pin d19
7805801T0
analogue meters or dials
0401
7
18
Reguloron IA
ring diodes 'n a 20 pin dual-line package. Ideal for solid
I9p
I9p
2417
DECADE
/'
NEW LED linear Cursors
each device c0n1000 10 light
47p
BSp
377/2
MCI357
£1.60
MCI358
(CA3065) £1.23
MCI375
£1,56
MCI 455(555T) 65p
MCI 456CG £1.77
MCI 458CPI
89p
MC1468G £2.30
555
30p
Regulators 5004nÁ
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7
{1 .06
CD4511AE
004528ÁE
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Regulators IOgmA
78705ÁW0 718Á625A1 9017
78L12AWC 11BA625B1 90p
%BL 158 WC ITBA625C
91717
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7517
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51-4'6552-?
MCI351
MC1352
44p
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28o
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8517
£2.10
£2.52
£4.34
£4.85
£1.60
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£1.94
MCI312P
MCI 31217
MC1314P
MCI 317P
MCI 327P
91.69
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1-ç
E6.59
87.94
CA3045
CA3046
CA3053
CA3065
CA3075
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CD4081 AE
C8408764E
004 868E
28p
m6
£1 .41
9417
41.13
1i1
£1.85
CI
200
Pd
£6.59
AY -5 -3507
AY- 5-4007
69p
66p
4417
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2N5777
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£3.30
SN:6003N
41.98
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3N26227NIMC 1327/
£I .86
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8N'6550- ?(7AA550)898
£1.12
CÁ2111
753
25v
Velcro
8v
II
250 mA
£3.95
3917
pin dips
i
25v
LM3900
LM3909
MC1303L
MC1306P
4517
741
Vcbo
LM2111
El .44
710116 pin dip!
pin dips
74' 114 pin dip,
748 8 pin dip,
748110 -99,
748 116 pin dip,
Pre
1
3917
041: TO-991
-Amplifiers
Pre-Amplifier
Viceo
47p
38p
650
s
F.C.
£6,93
710110 -991
741
E1.02
CI.IS
6817
2231TO -991
723 /14 pin dip
17N0í0 -DARLINGTON
6517
18
1
AY -I -5051
AY -5 -1224
EI.29
711110 -991
711 (Id pin dip';
720 /A. M.Rod;o
I.0
Instrument Amplifier IB;ie0
General Purpose Mini Amplifier
D.0 Canrrol led Gain Control
Micro-mini radio 12 I,C's!
£1,86
EI.17
£2.32
£2.32
CI .76
710
Tape
Power Driver
14p
El .69
E2.12
3l17
7517.
Audio I.C. Booklet
Page A4
Audio
5
14p
EI.46
L ?. 78
pin
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8
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84p'
£2.01
EI .49
£2.78
C04052AE
CD4056AE
'
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i1 .75
.24
36 pin 39
FREE with purchases of
.'s wortk £I. or more
3517. if sold alone) Contains circuits
and pin connection
15
Amplifiers 250ns
W to 20 worn
s
EI .2?
5917
EI
8
Linear
53p
E1
1175
2617.
AY- -0 ?I2
55P
819
709 (10-991
9091.14 pin dips
supplied
'1s
ITO -99rí
(14 pin dip,
703 IRF /IF Amp
FREE CIRCUITS
Our
i8 pin d'1p1V
555
709 I69in dip)
sY
pin 30p.
28
555
556
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8217'
£1.53
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pin 15p
44p
93p
1717
£2.09
CD404 ?AE
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05'
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19p
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CD4030AE
004035ÁE
004040ÁE
14
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£1.31
81.45'
I7p
19p
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CDIO ?6ÁE
CD4027AE
C04028AE
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6517
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CD40?4AE
46p
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80p
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004021AE
C04023AE
C0407 ?AE
14p
50p
48p
55p
CD4018AE
LINEAR
V. ips
of 100 Just snip oil what
you need. 65p per strip
Dual sin lane
8 pin 1317
14 pin
16 pin 15p
14p
1717
C1.46
pin
Pin Sackers,
1-'.46 ' EI.I7
75
CD4017AE
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IJp
19p
004013ÁE
094014ÁE
00401 SAE
004016ÁE
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CD4049
CD4050
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19p
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75
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2417
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CD4010AE
electronics
L
loop
I7p
19p
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/p.
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17.17.
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Just add
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132 Pages
The 4600
SYNTHESISER
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DISCO
for this brilliantly designed synthesiser,
including all the PCB's, metalwork and a drilled and printed front
panel, giving a superb professional finish. Opinions of authority
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Leaflet MES52, price 15p, describes the
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(:lijil
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Solid -state switching and new footages along with a pedal board
and a further extension of the organ's range are shown in
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